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Hi There! Thanks for checking in for today's blog - I'm off today, Halloween Monday, October 31, but will be back into work again bright and early Tuesday morning, and the blog will resume then. So be sure to check back tomorrow and we'll pick up right where we left off, but in the meantime, I'll keep my forecast updated at left. See you here tomorrow - and have a terrific Monday!
Matt
Welcome to the weather blog! While the web address has changed, the blog will still be the same Monday through Friday discussion - with some improvements! Over the course of the next few weeks and months, you'll find me experimenting and adding new features. Maps, pictures, and other multimedia are enhancements I'm hoping to be able to make as I learn more about how to maximize the new site. Format will be similar to the old version - you'll find a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. If no technical discussion is available when you check in during the morning, check back later as it often comes after the Weather Summary - I try to indicate at the end of the general weather summary when/if a technical discussion is coming. My email is contact@mattnoyes.net. This blog is for you, so I hope you enjoy it! -Matt Noyes
For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net
Matt's Weather Summary: Welcome to your weekend! As our showers of rain and snow from Saturday wind down in Eastern New England, you can still monitor how heavily the precipitation is falling in your town over the weekend by monitoring the radar imagery off of my homepage at www.mattnoyes.net.
With high pressure pressing east out of the Ohio River Valley on Sunday, skies will clear and warmer air will begin to move in, a little at a time. In fact, a blend of sun and clouds should help to push temperatures into the 50's in most areas. By Monday, warmer air continues to filter northeast into our six-state region, and most of us will fall either side of 60! By the middle of next week, here's some food for thought: A very strong storm center that moved off the Asian coastline a couple of days ago continues to move over the Bering Strait and into the Aleutian Islands across the Northern Pacific Ocean. Because this storm is moving over a data-sparse area (the ocean), our forecast guidance products will not handle it well until it moves back over land. But as mentioned yesterday, it seems to me the pattern will be favorable for this storm to dive south to the Gulf of Mexico next week, gather moisture, then result in a potentail coastal storm by the middle to end of next week, sometime around the 3rd of November. While it's still very early, and this is nothing more than conjecture at this stage of the game, it is worth paying attention to.
Meanwhile, record-breaking 23rd tropical storm of the season, Tropical Storm Beta, continues to gradually strengthen, and should reach hurricane strength sometime during the day Friday. The storm is expected to move into Central America over the next couple of days, bringing flooding rains to Honduras and Nicaragua.
Have a wonderful weekend!
Technical Discussion: Friday's is posted below.
Matt
Matt's Technical Meteorological Discussion: Updated Friday, October 28 at 10:00 AM
Short term fairly straight-forward with abundant low level moisture enough to maintain stratocumulus deck, even where sun burns thru for awhile. Winds shift NE late, esp in Southern NewEng as 1020 mb and deepening low off NC coastline moves NE and bubble of high pressure locks in to our west. This NE flow will also aid in keeping low level moisture in place. With only limited sun and cool air over us, temps hold in 40's most areas once again.
Clouds thicken overnight in Southern NewEng as warm and moist advection commences over low-level cool dome. A few rain showers are possible as advection kicks in this evening over Cape Cod, though most of the showers should hold off until around 00Z. With good agreement among the guidance on 500 mb low slowing a bit more as it moves E, have to buy into solution of bringing precip into Eastern NewEng Fri Ngt thru Sat, though I'm still not really sold on this being anything more than a nuisance event for primarily the coastal plain. The problem with this slower upper low movement actually has a greater effect during the day Sat as favorable diffluent on north side of 500 mb circulation and unstable cool pool aloft end up over Eastern NH/MA and this should keep a wrap-around, deformation band going with periods of rain for eastern sections, but it's important to note that we have virtually no low level dynamics working for us - it's really only what's going on aloft. Still, I could see .5-.75" with locally higher in a thin band under the best diffluence which would run on a SW to NE orientation even though the main low and precip shield is offshore. This diffluence is very strong at 300 mb and will drive precip under it, but I think it's important to realize that with a lack of low level dynamics - no speed/directional convergence, warm and moist advection Fri Ngt quickly becomes cold and dry advection Sat as flow goes NW at 850 - it's going to be hard to generate a widespread area of precip outside of this deformation band, and quite difficult to drive precip all that far NW. Enuf cold air in place just off the ground with 850's well below zero and 925's coming below zero with upward vertical motion that we may see some snowflakes mixing in from SE NH to Merrimack Valley to Worcester Hills - and snow showers would be the likely ptype if precip ends up reaching as far NW as the models prog it to (I have doubts) into the Lakes Region. In the hilly terrain of NH and the higher terrain of the Northern Worcester Hills, hilltops may see a coating on grassy surfaces but for most areas the boundary layer temps are just too warm to overcome enuf for flakes to stick.
All should eject quickly east Saturday night and Sunday still looks fine as high pressure noses in from west. Warm tongue of air progged to move in from NW across NewEng and this warm toungue produced temps around 70 in narrow slice of Nrn Plains Thursday. Still, with low level cold air slow to scour out, and cooler moderation this warm tongue as it outruns deepest warm advection, banking on temperatures averaging cooler than guidance on Sunday. Southwest flow on Monday keeps the low level warmth streaming in but next shortwave isn't far away and clouds come streaming in later in the day, as well. Didn't go nuts on temps as a result.
In the longer range...the low I discussed Wednesday that was coming off the Asian coastline is now beginning to interact with the Aleutian Low. This weekend it will launch a strong slug of vorticity eastward, and it may take until late in the weekend before that upper level circulation comes into an area of enough data collection for the models to pick up on the potential. I'd expect by Sunday at least one or two of the medium range models should start to pick up on a potential strong coastal storm for the middle to end of the week - centered around Nov. 3 - which taps Gulf moisture before going negatively tilted off the East Coast as it nears NewEng. But with no model support - even the Ensembles have lost this - I can only speculate...and wait for the models to realize the strength of this disturbance as it emerges from their blind spot. We'll see - could be fun to watch.
Have a great weekend.
Matt
Welcome to the weather blog! While the web address has changed, the blog will still be the same Monday through Friday discussion - with some improvements! Over the course of the next few weeks and months, you'll find me experimenting and adding new features. Maps, pictures, and other multimedia are enhancements I'm hoping to be able to make as I learn more about how to maximize the new site. Format will be similar to the old version - you'll find a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. If no technical discussion is available when you check in during the morning, check back later as it often comes after the Weather Summary - I try to indicate at the end of the general weather summary when/if a technical discussion is coming. My email is contact@mattnoyes.net. This blog is for you, so I hope you enjoy it! -Matt Noyes
For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net
Matt's Weather Summary: Welcome to your weekend! As the day progresses on Saturday, a few showers will continue to slowly advance northwestward, extending from Hartford to Worcester to Southeastern NH, points south and east and along the coast of Maine by afternoon. Steady rains will fall for a time from the immediate coastal locales of Southern Maine, southward through the immediate coastal plains of New Hampshire and Massachusetts. Things wind down Saturday night as the storm pulls quickly away from New England, and overall, I'm still not convinced on this system being much more than a nuisance weather-maker for some of Eastern Southern New England. Regardless, you can check how heavily the rain is falling in your town over the weekend by monitoring the radar imagery off of my homepage at www.mattnoyes.net.
With high pressure pressing east out of the Ohio River Valley on Sunday, skies will clear and warmer air will begin to move in, a little at a time. In fact, a blend of sun and clouds should help to push temperatures into the 50's in most areas. By Monday, warmer air continues to filter northeast into our six-state region, and most of us will fall either side of 60! By the middle of next week, here's some food for thought: A very strong storm center that moved off the Asian coastline a couple of days ago continues to move over the Bering Strait and into the Aleutian Islands across the Northern Pacific Ocean. Because this storm is moving over a data-sparse area (the ocean), our forecast guidance products will not handle it well until it moves back over land. But as mentioned yesterday, it seems to me the pattern will be favorable for this storm to dive south to the Gulf of Mexico next week, gather moisture, then result in a potentail coastal storm by the middle to end of next week, sometime around the 3rd of November. While it's still very early, and this is nothing more than conjecture at this stage of the game, it is worth paying attention to.
Meanwhile, record-breaking 23rd tropical storm of the season, Tropical Storm Beta, continues to gradually strengthen, and should reach hurricane strength sometime during the day Friday. The storm is expected to move into Central America over the next couple of days, bringing flooding rains to Honduras and Nicaragua.
Have a wonderful weekend!
Technical Discussion: Yesterday's is posted below.
Matt
Matt's Technical Meteorological Discussion: Updated Friday, October 28 at 10:00 AM
Short term fairly straight-forward with abundant low level moisture enough to maintain stratocumulus deck, even where sun burns thru for awhile. Winds shift NE late, esp in Southern NewEng as 1020 mb and deepening low off NC coastline moves NE and bubble of high pressure locks in to our west. This NE flow will also aid in keeping low level moisture in place. With only limited sun and cool air over us, temps hold in 40's most areas once again.
Clouds thicken overnight in Southern NewEng as warm and moist advection commences over low-level cool dome. A few rain showers are possible as advection kicks in this evening over Cape Cod, though most of the showers should hold off until around 00Z. With good agreement among the guidance on 500 mb low slowing a bit more as it moves E, have to buy into solution of bringing precip into Eastern NewEng Fri Ngt thru Sat, though I'm still not really sold on this being anything more than a nuisance event for primarily the coastal plain. The problem with this slower upper low movement actually has a greater effect during the day Sat as favorable diffluent on north side of 500 mb circulation and unstable cool pool aloft end up over Eastern NH/MA and this should keep a wrap-around, deformation band going with periods of rain for eastern sections, but it's important to note that we have virtually no low level dynamics working for us - it's really only what's going on aloft. Still, I could see .5-.75" with locally higher in a thin band under the best diffluence which would run on a SW to NE orientation even though the main low and precip shield is offshore. This diffluence is very strong at 300 mb and will drive precip under it, but I think it's important to realize that with a lack of low level dynamics - no speed/directional convergence, warm and moist advection Fri Ngt quickly becomes cold and dry advection Sat as flow goes NW at 850 - it's going to be hard to generate a widespread area of precip outside of this deformation band, and quite difficult to drive precip all that far NW. Enuf cold air in place just off the ground with 850's well below zero and 925's coming below zero with upward vertical motion that we may see some snowflakes mixing in from SE NH to Merrimack Valley to Worcester Hills - and snow showers would be the likely ptype if precip ends up reaching as far NW as the models prog it to (I have doubts) into the Lakes Region. In the hilly terrain of NH and the higher terrain of the Northern Worcester Hills, hilltops may see a coating on grassy surfaces but for most areas the boundary layer temps are just too warm to overcome enuf for flakes to stick.
All should eject quickly east Saturday night and Sunday still looks fine as high pressure noses in from west. Warm tongue of air progged to move in from NW across NewEng and this warm toungue produced temps around 70 in narrow slice of Nrn Plains Thursday. Still, with low level cold air slow to scour out, and cooler moderation this warm tongue as it outruns deepest warm advection, banking on temperatures averaging cooler than guidance on Sunday. Southwest flow on Monday keeps the low level warmth streaming in but next shortwave isn't far away and clouds come streaming in later in the day, as well. Didn't go nuts on temps as a result.
In the longer range...the low I discussed Wednesday that was coming off the Asian coastline is now beginning to interact with the Aleutian Low. This weekend it will launch a strong slug of vorticity eastward, and it may take until late in the weekend before that upper level circulation comes into an area of enough data collection for the models to pick up on the potential. I'd expect by Sunday at least one or two of the medium range models should start to pick up on a potential strong coastal storm for the middle to end of the week - centered around Nov. 3 - which taps Gulf moisture before going negatively tilted off the East Coast as it nears NewEng. But with no model support - even the Ensembles have lost this - I can only speculate...and wait for the models to realize the strength of this disturbance as it emerges from their blind spot. We'll see - could be fun to watch.
Have a great weekend.
Matt
Welcome to the weather blog! While the web address has changed, the blog will still be the same Monday through Friday discussion - with some improvements! Over the course of the next few weeks and months, you'll find me experimenting and adding new features. Maps, pictures, and other multimedia are enhancements I'm hoping to be able to make as I learn more about how to maximize the new site. Format will be similar to the old version - you'll find a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. If no technical discussion is available when you check in during the morning, check back later as it often comes after the Weather Summary - I try to indicate at the end of the general weather summary when/if a technical discussion is coming. My email is contact@mattnoyes.net. This blog is for you, so I hope you enjoy it! -Matt Noyes
For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net
Matt's Weather Summary: New England weather here on the ground will be fairly quiet the next couple of days, with our strong nor'easter pulling well east of the six-state region, and an area of high pressure slowly nudging eastward across the Great Lakes and Ohio Valley. Sandwiched between these two systems, our wind will blow from the north and northwest, keeping a chilly flow of air into New England, but winds should not gust as high as Wednesday. The good news is that this northerly wind direction keeps dry air filtering into New England, and a blend of sun and clouds will prevail for most of us, except in the mountains of Northern Vermont, New Hampshire and Maine where snow showers will crop up each afternoon Thursday and Friday. Thursday night will likely be even colder than Wednesday night was, with widespread lows in the 20's and 30's, and another round of frost.
But while the weather is quiet at the surface, it's quite busy aloft. Dropping south out of Canada are a series of disturbances at the jet stream level - that high-altitude, fast river of air that steers our storm systems and acts as a thermostat for the atmosphere, separating cold air to the north from warm air to the south. The jet stream has bubbled up as a ridge in the Western United States, and then drops sharply to a dip, or trough, here in the Eastern U.S. This ensures that while most of the nation enjoys relatively warm and dry weather, we'll continue to see disturbances dropping into this trough out of Canada, pulling down cool air and keeping the weather a bit unsettled. As these disturbances congregate off the Eastern Seaboard on Friday, yet another coastal storm will develop. This one, however, should move farther to the east than our storm from the beginning of the week, and also will be much weaker in intensity. Still, it's likely to come close enough to bring a gray and showery afternoon to Cape Cod and the Islands, closest to the storm center. Now imagine if the storm tracks just 50-75 miles farther west - a small amount on the scale of global weather. This would carry showers into much of Eastern Massachusetts and Eastern New Hampshire. While right now I'm optimistic that the showers will stop their westward progression at Cape Cod, the honest forecast is to let you know we are watching the possibility of a more westward advancement - that would bring showers into Eastern MA and Southeastern NH Saturday afternoon and evening.
Regardless, the storm will move east by Saturday night, and all of us should enjoy clearing and a decent day on Sunday. Warmer air nudges into New England by Halloween, bringing high temperatures near 60, and trick-or-treating temperatures should fall in the upper 40's and lower 50's with dry weather. By the middle of next week, here's some food for thought: Yesterday a very strong storm center moved off the Asian coastline and over the Pacific Ocean. Today, this storm continues to move across the Pacific, and will not be handled well by our forecast guidance products until it moves back over land - thanks to lack of good meteorological data over the oceans. Still, it seems to me the pattern will be favorable for this storm to dive south to the Gulf of Mexico next week, gather moisture, then result in a potentail coastal storm by the middle to end of next week, sometime around the 3rd of November. While it's still very early, and this is nothing more than conjecture at this stage of the game, it is worth paying attention to.
Meanwhile, in the tropics, the tail end of the powerful cold front I mentioned yesterday has indeed resulted in the development of a tropical system. Last evening, Tropical Depression #26 formed, and early Thursday morning the National Hurricane Center deemed this storm to be a further record-breaking 23rd tropical storm of the season, Tropical Storm Beta. The storm is located east of Nicaragua as of this writing, and is expected to move into Central America over the next 48 hours, bringing flooding rains to Honduras and Nicaragua.
Enjoy your Thursday.
Technical Discussion: Lots to do around the station today and a school visit later, so chances are good it'll be a freshening up of yesterday's thoughts that comes by early afternoon.
Matt
Welcome to the weather blog! While the web address has changed, the blog will still be the same Monday through Friday discussion - with some improvements! Over the course of the next few weeks and months, you'll find me experimenting and adding new features. Maps, pictures, and other multimedia are enhancements I'm hoping to be able to make as I learn more about how to maximize the new site. Format will be similar to the old version - you'll find a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. If no technical discussion is available when you check in during the morning, check back later as it often comes after the Weather Summary - I try to indicate at the end of the general weather summary when/if a technical discussion is coming. My email is contact@mattnoyes.net. This blog is for you, so I hope you enjoy it! -Matt Noyes
For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net
Matt's Weather Summary: What a storm! And it continues in parts of Northern New England. Many of you wrote to me with your weather observations during the storm, and I am extremely appreciative - it was your observations that helped me to know higher terrain saw a change to snow some 5 hours earlier than I was expecting, and I was able to incorporate your observations in my on-air presentation of the forecast.
As the storm center itself pulls east of New England, winds have come around to the northwest and will gust over 30 mph in most areas. For those of us in Central, Southern and Eastern New England, this direction actually will help us to break up the clouds through the day on Wednesday. Winds from the northwest are called "downsloping" winds in these areas - as they slope down the mountains and hills of Northern and Western New England. Air that descends in elevation tends to warm up a bit, and dry out a bit, due to changes in barometric pressure with a change in altitude. As a result, this slightly warmer and drier air should allow the clouds to break for some sunshine in many areas. Those of us who live in the mountainous terrain of Northern and Western New England, however, find a very different Wednesday, as our northwest wind is forced to slope UP the mountains, not down them, and this is the perfect setup to allow clouds and precipitation to linger. So, while most of the snow was winding down at midday, it may fire up again this afternoon and overnight Wednesday night, and a few additional inches are possible in those areas that have already seen some accumulation.
The remainder of New England will find partly cloudy skies and cold temperatures Wednesday night. Thursday and Friday a strong disturbance at the jet stream level will drop over New England, and the weather will remain cool, with more clouds than sun. The reasoning for this is that the jet stream - that high-altitude fast river of air that steers our storm systems and acts as a thermostat for the atmosphere, separating cold air to the north from warm air to the south - has bubbled up as a ridge in the Western United States, and then drops sharply to a dip, or trough, here in the Eastern U.S. This ensures that while most of the nation enjoys relatively warm and dry weather, we'll continue to see disturbances dropping into this trough out of Canada, pulling down cool air and keeping the weather a bit unsettled. The good news is that, with limited moisture, I'm not expecting much more precipitation than mountain flurries and snow showers on Thursday and Friday, but while most of us will stay dry, we will see an increase in clouds each afternoon. By Saturday and Sunday, this disturbance will become better defined and develop a storm center over the ocean, southeast of New England. The relieving news is that it looks right now like this storm center will be just far enough south and east of us to spare us from its effects, leaving us with a dry and mostly sunny weekend, but we have to acknowledge the fact that the storm won't be far away, and I am going to keep an eye on this, as a closer pass would bring weekend windswept rains.
Meanwhile, in the tropics, the tail end of the powerful cold front that helped to spawn our nor'easter, has dropped all the way south of Cuba! In addition to being a remarkable journey southward for this front, it also may prove to be problematic in the tropics. The front has stalled near Cuba, and oftentimes a stalled and dying cold front in the tropics can be the impetus for a new tropical system to develop if atmospheric conditions are right. A large blossoming area of thunderstorms has already developed on the tail of this cold front, and a new tropical storm may develop south of Florida over the next three or four days. Should this system develop, the pattern would be favorable for it to move northward, and the eastern coast of the sunshine state may find itself under the gun again, but it's much too early to speak with certainty on this scenario.
Have a good Wednesday!
Matt
Matt's Technical Meteorological Discussion: Updated Wednesday, October 26 at 2:00 PM
Overall pattern features persistent trough to stay established along East Coast over the next month or so. There will, of course, be exceptions to the rule through the period when ridging will build in for a day or two ahead of strongly digging shortwaves, or when zonal flow will prevail during these short transitions, but overall troughing will be found through at least the third week of November, as the Aleutian Low continues to pulse, keeping the ridge built across the nation's midsection and Intermountain region.
In the immediate term, while our upper level low departs, its effects linger, as new Canadian energy dropping south from Canada digs in its place and keeps the trough well defined over New England for the next few days. The result is to find downsloping flow continuing to dry our favored Southern/Eastern areas in NW low level flow today with winds gusting over 30 mph from the NW, then as the new energy drops in Thursday and Friday, it stays positively tilted long enough to spare us anything signficant, but holds enough energy to keep plenty of clouds bubbling up across all of NewEng Thu and Fri. In the meantime, the snow falling across Northern NewEng has been falling apart, but I actually think as the upper, mid and low level flows align from the NW, we may see it fire up again, and that could spell a few late afternoon into overnight inches in the mountains.
Most areas drop into the 30's - certainly some 20's in Northern NewEng and perhaps even in Southern NH/VT/North Central MA in our deeper valleys. Indications are for low level moisture to be abundant enough for clouds to fill back in Thursday as the next shortwave drops into the trough from Canada - and most areas will be mostly cloudy by afternoon. This, combined with continued cool surface flow, keeps highs in the 40's, 30's north. Mountain flurries and snow showers are likely. A very similar situation on Friday with a shortwave dropping into the trough and enough low level moisture to crank the stratocumulus deck again, with additional flurries and snow showers in the mountains.
The weekend is about as close as they come! The trough only slowly trudges eastward while the multiple shortwaves dropping into it consolidate to deepen an upper low directly over New England. This will provide enough lift to generate a surface low pressure center, as has been advertised by the GGEM and GFS Ensembles for the past few days. The problem here is, of course, how close does the coastal creature come to NewEng? First of all, let's focus on what we know - this storm is certain to maintain a northerly low level flow and therefore the cool air keeps coming through the weekend. I don't expect the coastal low - whether it affects NewEng or not - to move away quickly, and therefore both days should see the effects of this cool surface flow and even with sun it would be hard to get much above the lower 50's on average. As for where the surface low ends up developing and tracking, my thinking right now is to keep the low offshore enough to avoid significant effects for NewEng. My reasoning is that we're losing the amplified ridge to our west that was present for this past storm - the ridge was amplified and holding tough to our west, which allowed our trough to amplify as well. By this Friday, we'll already see a developing fast zonal flow coming in from the Pacific, and this will beat down the ridge over the Upper Great Lakes, likely allowing the pattern to move just long enough to shift the upper low over NewEng by Saturday. While the surface low eventually will become wrapped up into the upper low, and I'm willing to acknowledge that the upper low may move slower than forecasted by the guidance as it moves east of NewEng, I'm doubtful it will slow down enough for the surface low to be wrapped far enough westward to give NewEng a significant blow from this next coastal creature. Of course, whether or not far eastern areas and esp Cape Cod are nicked by showers from this feature it's still very early to say. Also, IF the models are too quick in breaking down the ridge to our west, that will slow the eastward progress of the upper low, and thereby allow the surface low to track closer to the coast. So, for now I'm acknowledging the coastal storm on-air but also mentioning that my current thinking is it probably stays offshore, though I've been explaining that 100-200 miles isn't much in the scope of weather systems.
In the longer term, a big player in our weather by the first week of November the way I see it is an intense upper level low just coming off of China. This low is tremendously strong - sub 510 gpm - and the strongest upper low in the Northern Hemisphere with the exception of the polar vortex, located north of Siberia currently. This Chinese low is just now ready to emerge over the Pacific and will enter the Aleutian low south of Alaska this Saturday into Sunday. The result will be to kick a substantial vorticity maximum out of the Aleutian low and drive it eastward into the fast and nearly zonal flow over Western Canada. This vorticity maximum will dive rapidly southeast over the Northern Midwest and pick up abundant Gulf moisture as it swings through the mean trough position - located near the OH River Valley. With a strong upper low south of Iceland, an upstream ridge east of the Canadian Maritimes will be in place, and this should favor further amplification of the potent vorticity maximum as it rounds the base of the trough, and a negative tilt should be the result as the system draws up the Eastern Seaboard for the potential of a strong coastal low, especially for NewEng. At this point, I don't see enough cold air in the Western Hemisphere to support a widespread snow threat, but there is evidence of a bubble high northeast of NewEng and this would set up a snow threat for Northern NewEng with what would be a November 3 nor'easter. I should say that I do expect the models to lose this system once it comes over the Pacific, so don't be surprised if it disappears for awhile, then reappears in a few days as the vort kicked out of the Aleutian low comes over land in Western North America.
That's all for today.
Matt
Welcome to the weather blog! While the web address has changed, the blog will still be the same Monday through Friday discussion - with some improvements! Over the course of the next few weeks and months, you'll find me experimenting and adding new features. Maps, pictures, and other multimedia are enhancements I'm hoping to be able to make as I learn more about how to maximize the new site. Format will be similar to the old version - you'll find a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. If no technical discussion is available when you check in during the morning, check back later as it often comes after the Weather Summary - I try to indicate at the end of the general weather summary when/if a technical discussion is coming. My email is contact@mattnoyes.net. This blog is for you, so I hope you enjoy it! -Matt Noyes
For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net
Matt's Weather Summary:
TUESDAY UPDATE: Very busy on air today with continuous storm coverage on NECN. Thoughts have not changed from yesterday. I'll post when and if I have time today, but yesterday's is still applicable.
A major storm will be affecting New England over the next 36 hours. This storm will bring a series of hazards, each of which will be outlined here. First of all, the setup is this: Hurricane Wilma continues to move northeast and has been moving remarkably fast for a storm so far south - traveling at over 25 miles per hour as she departs the Florida coastline. Moving back over warm water east of Florida, Wilma will have the potential to hold her category two hurricane status. It's possible she could even strengthen a bit briefly, though once she encounters stronger winds aloft, this "shear" (differing wind speed and direction with height) will abruptly halt the strengthening process, likely resulting in a weakening of the storm.
At the same time, Wilma will begin to interact with cooler air aloft, and she will start to lose tropical characteristics, becoming what we refer to as an "extratropical storm". When storms become extratropical, a few important changes occur to the heavy rain and wind that was formerly concentrated around the eye. The first change is that the eye becomes less defined - transitioning to a shape more like a comma than a concentric circle. At the same time, the heaviest rainfall begins to shift north and west of the storm center, and the wind field expands by hundreds of miles - deteriorating a tightly packed center but expanding the effects of high winds and heavy precipitation over a much larger area.
But it won't be all of Wilma that arrives into New England. In fact, here's how things will break down: Monday finds breaks of sunshine in Central and Southern New England continuing to fade behind increasing and thickening clouds. Northern New England began the day cloudy and will finish it cloudy, with spritzes of rain and snowflakes off and on through the day. Farther south, along the Mid-Atlantic coastline, a new wave of low pressure will gradually take shape throughout the day. By this evening, this newly developed storm center will be sitting off of Virginia Beach, and will tap just a piece of the substantial energy and moisture that will be racing by with Hurricane Wilma. Nonetheless, this piece of energy will be enough to really get this new area of low pressure cranking - and as the storm begins to move northward along the Atlantic Seaboard, rains will spread northward, as well. Showers are likely to develop Monday evening, and rains will move in, heavy at times, Monday night into Tuesday as this new center of low pressure pushes north and toward New England.
By very early Tuesday morning, winds will begin gusting upwards of 40 mph along the South Coast of New England as the coastal storm center draws near. From dawn Tuesday to mid-afternoon, northeast winds may gust as high as 65 mph along the coastline - a few of you with personal weather stations along the immediate coast may gust over 70 mph, nearing hurricane force - and this will be enough to down trees and powerlines from an already saturated ground, as well as result in some damage to shingles on coastal homes. Folks in Eastern New England and especially along our coastlines should ensure generators are working, fill up the gas tanks of vehicles and any equipment needed to clear fallen trees, secure vessels in preparation for possible hurricane force gusts, and mariners should most certainly stay in port. Farther inland, winds will still gust to 45 mph, and this may be enough for an isolated power outage through the interior. Rains will fall heavily through at least the first half of Tuesday, dropping 2-4" widespread through Central and Southern New England, and this will be enough rain to send most rivers back into flood beginning later Tuesday. High tides come at about 5 AM Tuesday morning, and again around 5 PM Tuesday evening. The tide is not astronomically high enough to cause more than just splashover in the morning, though minor to moderate coastal flooding is possible on east and northeast facing shorelines Tuesday evening through almost all of New England as waves in excess of 20 feet offshore combine with the continuous and strong onshore northeast flow. Most of New England will be warm enough for rain through Tuesday, though the higher summits of Vermont, New Hampshire and Maine will see a mostly snow event with substatial accumulation of greater than 20" of heavy wet snow in elevations above 2700 feet which will down many trees and power lines. Elsewhere in the North Country, rain will gradually change to snow Tuesday afternoon into Tuesday night - at highest elevations first - and average snowfall totals will run from 3 to 5 inches, but again...the higher up you are in elevation, the more snow you'll receive, and vice versa for the deepest valleys.
Most of the damaging winds and coastal flood threat along our coastlines will diminish after Tuesday evening, but not before likely leaving a decent amount of damage to coastal communities - especially from Quincy, MA, points northward into coastal New Hampshire. The snow in Northern Vermont and New Hampshire will likely continue into Wednesday. Snow may even accumulate into the Northern Berkshires and far Nothern Lakes Region, so please tune into NECN to see our latest accumulation forecast. Others of us...even in Southern New England...may see the storm end Wednesday as a collection of flurries or light snow showers, especially in the hilly terrain.
By Wednesday afternoon, Southern and Central New England may still be cloudy, but will be drying out, while the mountains of the North Country may still be contending with lingering snow showers. Thursday looks brighter for most of us - though still cool with average high temperatures in the 40's - before a weak cold front moves through overnight Thursday night, perhaps with a few flurries in the Northern Mountains. This will reinforce cool air for Friday, and while the sun will return, temperatures will remain held in the 40's.
Please continue to follow this strong and damaging storm (at least for coastal communities) with us on NECN. For those of you who are interesed, I'll be one of the guests appearing on WGBH Boston's "Greater Boston" with Emily Rooney Monday evening at 7 PM, discussing this storm.
All My Best,
Matt
Matt's Technical Meteorological Discussion: Updated Monday, October 24 at 2:00 PM
Quite busy as you'd expect so this will be relatively brief.
Expecting rapidly northward advancing cloud shield to continue moving in with associated rain shield reaching South Coast this eve and the rest of NewEng overnight. Rain should fall heavily through the overnight with significant warm and moist advection underway. While a general swath of rian should overspread most of the Southeastern half of NewEng with embedded heavy downpours, a heavier swath of rain will set up along the tightening low-level baroclinic zone evident in 925 mb temps. A 50-70 knot 925 mb jet feeds into this from Mon Ngt thru Tue afternoon and this combination of speed convergence and thermal advection should result in significant low level lift to really crank out a band of heavier precip. Exact placement of the band depends on track of surface low, but seems to be general agreement on this setting up in Central or Eastern Southern NewEng. It's in these areas where the general 2-4" rainfall may be exceeded.
Overall still expecting Wilma to go east of NewEng into Nova Scotia and coastal low spinning up off VA coastline this eve trudges north pulling in low level energy and moisture from Wilma. The 12Z NAM has thrown a monkey wrench into all of this by dragging Wilma westward and merging her into the coastal low - GFS doesn't bite and neither do I for now - really want to get a good grasp of 12Z runs before changing the tune I've been singing today. Interesting to note that this 12Z NAM solution not only would crank out plenty more widespread snow across Northern NewEng but also brings an 85 kt 925 mb NE jet into the ECoast of MA! Even without this solution, though, still looking at 70 knot low level jet feeding in and we should be able to mix at least some of this down the surface - so 50+ knots looks like a lock, and right now I've been putting the lid on at 65 mph but acknowledging that 70+ could be recorded at personal weather stations along the coast. This kind of wind is enuf for damage in coastal communities, though farther inland...winds will gust to 45 mph and this is only enuf for isolated tree/power line damage. Coastal flood threat is managed well by WFO Taunton - not a problem at 5 AM cycle because we need persistent strong winds to bring the seas in.
Snow is the next concern. Looks cold enuf for all snow above 2700 feet in elevation VT/NH and in these spots we'll find amounts of between one and two feet of heavy wet snow that will down power lines and snap some foliage-laden trees. Below 2700 feet, it looks like it's rain until later Tuesday afternoon, when wave deepens and begins to gradually shift east in longitude, allowing cooler air to spill around the back of the circulation and bring the freezing level crashing down. There will be some contamination of warm air around 700 mb esp from 18Z Tue thru 06Z Wed and this may retard descent and southward progression of snow, allowing for a period of sleet, though within bands of enhanced lift, dynamic cooling will offset this pocket of slightly above zero Celsius temps.
Interesting that as storm goes by, winds come SW and may still gust up to 50 or 55 mph on the South Coast of MA into Tue Ngt, but otherwise it looks like winds go below damaging criteria and precip intensity tapers in Southern NewEng Tue Ngt into Wed AM. Clouds linger in Southern NewEng most of Wed while upslope snows continue in association with upper level cool pool slowly wrapping thru the Nrn Mountains behind the circulation.
Looks like a break to start Thu, then shortwave and associated surface cold front come thru Thu ngt and this may touch off some flurries or snow showers in the North Country. Reinforcing shot of chilly in place but sun returns Fri.
Tomorrow will be interesting...and long. Good luck to all!
Matt
Welcome to the weather blog! While the web address has changed, the blog will still be the same Monday through Friday discussion - with some improvements! Over the course of the next few weeks and months, you'll find me experimenting and adding new features. Maps, pictures, and other multimedia are enhancements I'm hoping to be able to make as I learn more about how to maximize the new site. Format will be similar to the old version - you'll find a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. If no technical discussion is available when you check in during the morning, check back later as it often comes after the Weather Summary - I try to indicate at the end of the general weather summary when/if a technical discussion is coming. My email is contact@mattnoyes.net. This blog is for you, so I hope you enjoy it! -Matt Noyes
For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net
Matt's Weather Summary:
**Saturday morning update: Rain showers, unfortunately, have already been spreading north and east across Southern New England. The good news is that it won't be a continuous rain for several more hours, but it's a day like today - when things seem threatening sooner than expected or in a different location, etc. - for which I've created my main page (linked above). There will be some weekends I'll be out of town and unable to update my forecast on this page, but you can always follow the showers from the radar links across New England at the main page, and see what this means for your town. Have a wonderful weekend and stay dry! -Matt **
A late post today since I'm off from NECN for the day - likely no post this weekend unless significant weather warrants, then back to normal on Monday morning. Our protective bubble of cool and dry high pressure will keep encroaching rains south and west of New England Friday into Saturday. These incoming rains will be the product of the very same bundle of atmospheric energy that brought flooding rains and mudslides to Southern California and the Southwestern US the last few days. As this energetic upper level storm center moves slowly into the Ohio Valley, a new and quite vigorous disturbance will drop south out of Canada, and these two systems will merge over the Ohio River Valley. The result will be a large and powerful storm in the upper levels of the atmosphere to our west, and this will push increasing moisture toward New England, with high altitude clouds increasing Friday afternoon and evening.
By Saturday, as high pressure pulls away from New England, clouds will continue to thicken through the day with a push of warm and moist air pulsing northeast ahead of the aforementioned upper level storm. It appears as though rains will spread into New England by Saturday evening, with periodic rain Saturday evening and night. At this point, it still doesn't appear to me as though Saturday night's rains will be flooding, but that's not the whole story.
Sunday and Monday's weather are a bit trickier. Here's why: the powerful upper level storm to our west will pivot a slug of energy counter-clockwise around it's circulation on Sunday, sending this packet of energy hurling toward the Eastern Seaboard. This energy may be strong enough to keep rains going in the Northeast on Sunday into Sunday night - and some of that rain could be heavy at times. The delicate interaction between this energy and the primary upper level storm will help to determine just how long rain lingers in New England. As of this writing, Hurricane Wilma continues closing in on the Yucatan Penninsula through the Western Caribbean. While her intensity has been fluctuating due to restructuring processes inside the eye, she still is a strong Category 4 hurricane as of this writing, and has the potential to strengthen back up to Category 5 status as her eye restructures. Wilma has begun her gradual turn which should take her to the southwestern coast of Florida - now perhaps sometime on Sunday. Once Wilma crosses Florida, there is tremendous uncertainty as to how she will interact with our coastal wave of low pressure. If she's slow enough and misses to the south entirely, we'll feel little effects. If she comes a bit closer but still stays offshore, some of her moisture may be tapped to enhance rainfall amounts...especially during next week. If she becomes completely wrapped up in the storm, we'll be talking about a much larger and stronger storm for early next week, but at this point that's not the most likely solution...just something to watch.
Technical Discussion: None today...but if things look really interesting this weekend I'll post some thoughts. Otherwise, we'll pick up again on Monday.
Have a great weekend!
Matt
Welcome to the weather blog! While the web address has changed, the blog will still be the same Monday through Friday discussion - with some improvements! Over the course of the next few weeks and months, you'll find me experimenting and adding new features. Maps, pictures, and other multimedia are enhancements I'm hoping to be able to make as I learn more about how to maximize the new site. Format will be similar to the old version - you'll find a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. If no technical discussion is available when you check in during the morning, check back later as it often comes after the Weather Summary - I try to indicate at the end of the general weather summary when/if a technical discussion is coming. My email is contact@mattnoyes.net. This blog is for you, so I hope you enjoy it! -Matt Noyes
For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net
Matt's Weather Summary: I'll be off Friday...I still plan to write something up for you, but hopefully later in the day - that would mean I actually was able to sleep in...we'll see! :)
The latest energetic but fast-moving and moisture starved system to move through New England passed through without much fanfare, and as of Thursday morning the surface center of low pressure is moving east of Maine. Behind the disturbance, winds have shifted to the northwest and will blow at 10-20 mph with a few higher gusts as they carry colder air southward from Canada. In Central and Southern New England, a northwest flow of air glides down the mountains of Northern and Western New England, and this helps to further dry an already dry Canadian airmass, so plenty of sunshine is in the forecast. Across Northern New England, a northwest wind pushes up against the mountains, instead, and this will keep lots of clouds locked in the mountainous terrain on Thursday with periodic flurries and sprinkles.
With a bubble of high pressure - a center of fair weather - building southeast out of Hudson Bay, Canada, across the Great Lakes and into New England, winds will become light and skies will be clear in New England Thursday night. With a cool and dry airmass in place, these conditions will be nearly perfect for temperatures to drop, and most areas will find a killing frost through interior Southern New England with temperatures dropping into the 30's, and a hard freeze through parts of Northern New England. Here's a freaky and amazing story to share with you - one of our weather observers, Dick Whalen, lives in Natick, MA. On July 21, he called to let us know that the cicadas were singing, and that over the years he's learned that it's exactly three months from when the cicadas sing that the same location will see their first killing frost. Here we are, the eve of Friday, October 21 - exactly 3 months later - with a forecast for the first killing frost through interior Southern New England. Add that one to your notebooks!
Our protective bubble of cool and dry high pressure will keep encroaching rains south and west of New England on Friday, as well. These incoming rains will be the product of the very same bundle of atmospheric energy that brought flooding rains and mudslides to Southern California and the Southwestern US the last few days. As this energetic upper level storm center moves slowly into the Ohio Valley, a new and quite vigorous disturbance will drop south out of Canada, and these two systems will merge over the Ohio River Valley. The result will be a large and powerful storm in the upper levels of the atmosphere to our west, and this will push increasing moisture toward New England, with high altitude clouds increasing Friday afternoon and evening.
By Saturday, as high pressure pulls away from New England, clouds will continue to thicken through the day with a push of warm and moist air pulsing northeast ahead of the aforementioned upper level storm. It appears as though rains will spread into New England by Saturday evening, with periodic rain Saturday evening and night. At this point, it still doesn't appear to me as though Saturday night's rains will be flooding, but that's not the whole story.
Sunday and Monday's weather are a bit trickier. Here's why: the powerful upper level storm to our west will pivot a slug of energy counter-clockwise around it's circulation on Sunday, sending this packet of energy hurling toward the Eastern Seaboard. This energy alone will likely be strong enough to develop a storm center along the East Coast - which could bring very heavy rains sometime between Sunday afternoon and Monday afternoon. Right now, pinpointing the exact timing of the potentially heavy and flooding rain to more than that 24 hour window is quite difficult, given the delicate interaction between this energy...the primary upper level storm...and Hurricane Wilma. As of this writing, Hurricane Wilma is moving slowly toward the Yucatan Penninsula through the Western Caribbean. While her intensity has been fluctuating due to restructuring processes inside the eye, she still is a strong Category 4 hurricane as of this writing, and has the potential to strengthen back up to Category 5 status as her eye restructures. Wilma has been continuing on a west-northwest path and is expected to make a turn toward the north Thursday night into Friday, though this is later than originally anticipated. The longer it takes Wilma to make this turn, the more time she'll spend over the land of the Yucatan Penninsula, the more weakening she'll encounter, and the slower she'll move toward Florida. Eventually, though, it still appears as though Wilma will make landfall in the southwestern coast of Florida - now perhaps sometime on Sunday. Once Wilma crosses Florida, there is tremendous uncertainty as to how she will interact with our coastal wave of low pressure. If she's slow enough and misses to the south entirely, we'll feel little effects. If she comes a bit closer but still stays offshore, some of her moisture may be tapped to enhance rainfall amounts...especially by Monday. If she becomes completely wrapped up in the storm, we'll be talking about a much larger and stronger storm for early next week. I honestly don't think there's a meteorologist in the world, at this juncture, who can speak with complete certainty on how this will all play out, so please stay tuned to the updates as the interaction between Wilma and our storm closer to home plays out. Either way, a shot of heavy rains seems probable between Sunday and Monday afternoon.
Technical Discussion: Busy day today but perhaps some new ideas to supplement yesterday's long discussion.
Enjoy your Thursday!
Matt
Matt's Technical Meteorological Discussion: Updated Thursday, October 20 at 1:10 PM
In the short term the forecast remains fairly straight-forward. Cirrus clouds riding overhead well north of main axis of moisture and what will be a corridor of isentropic lift. This will continue periodically through Friday. Meanwhile, low clouds across the North Country, and with upslope flow and cold advection, this trend continues most of the day in the mountains. Dry air cools quickly tonight as winds slacken. Widespread 30's in Southern and Central NewEng, 20's across the far north.
Weekend thinking still is quite similar to what I put forth yesterday with regard to synoptics - the upper low is still forecasted to deepen quickly as the strong Canadian vorticity maximum joins forces in the area of lowered heights from the current slow-moving upper low in the Ohio Valley. This will pivot an area of vorticity toward the Eastern Seaboard which, in conjunction with warm and moist advection, will produce a band of rain for NewEng that will spread from SSW to NNE Saturday evening into Sunday. The heaviest burst of precip with this - at least initially - should come Saturday night. The GFS is going bonkers on amounts but appears to be suffering from convective feedback problems along a coastal boundary. The convective precip ramps up much too quickly, and I would not trust the amounts from the GFS at this time, and expect them to come down. Yesterday I'd conjectured somewhere between .5 and 1.0 inches as a widespread average - either side of the 1.0" mark might be a better estimate given the amount of warm and moist advection that will be ongoing Saturday night.
I'm carrying heavy rain potential in the forecast for Sunday evening through Monday evening. I've been expressing on-air that I think we'll see a period of heavy rain during this 24 hour period. My thoughts off-air are these: We know there will be a tremendous upper low to our west, and there is agreement on a signficant vorticity axis draped south of the low center by Sunday evening. Assuming this vort axis is going to pivot east as the entire upper low shifts east, this would bring significant energy to meet a meridional flow at the Eastern seaboard Sunday night for the development of a coastal low even though Wilma may still be farther south.
I think it's very important here not to miss the forest for the trees. Yes, looking at each operational model gives a different solution, yes the GFS paints a wet scenario for Saturday night into Sunday. But looking at the 500 mb prog is essential here, and the GFS uses its convective feedback (if I'm right on that) to prematurely shift the center of the upper low eastward, and this leaves the strong vort lobe still to pivot thru on a positive tilt and dampening, rather than following both the GFS and Canadian Ensemble members which suggest the center of the upper low holds back over Western Lake Erie through Monday, and keeping it farther west means a neutral or negative tilt as the vorticity axis swings east, and as this interacts with available moisture along the coastline in the increasing meridional flow, we should see generation of a coastal wave. It all sounds so easy now, doesn't it? No guarantee this is the correct solution, but given several days of agreement on slowing the upper low, and given the ridging bridging over the top of it suggesting this slow motion, as well, there seems to be no reason to flip flop with the operational models. Stick to the synoptic guns, my friends - and this means warm advection rains Saturday night that drop rainfall in a relatively brief period, limiting amounts. Then a break. Then a new coastal creature. Wilma? Still a maybe - see thoughts from yesterday's discussion - but with models not correctly picking up on overall pattern and placement of upper low, I wouldn't trust them on Wilma right now beyond a cut from SW Coast Florida and across the state.
I'm off tomorrow, but will probably put out some thoughts during the afternoon.
Matt
Welcome to the weather blog! While the web address has changed, the blog will still be the same Monday through Friday discussion - with some improvements! Over the course of the next few weeks and months, you'll find me experimenting and adding new features. Maps, pictures, and other multimedia are enhancements I'm hoping to be able to make as I learn more about how to maximize the new site. Format will be similar to the old version - you'll find a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. If no technical discussion is available when you check in during the morning, check back later as it often comes after the Weather Summary - I try to indicate at the end of the general weather summary when/if a technical discussion is coming. My email is contact@mattnoyes.net. This blog is for you, so I hope you enjoy it! -Matt Noyes
For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net
Matt's Weather Summary: I almost never offer my personal thoughts on anything in these posts, but I think it's necessary here regarding the Taunton Dam situation: The situation with the Whittenton Dam in Taunton should be monitored through NECN broadcasts or by monitoring the National Weather Service statements. For those of you with concerns and interests in the Taunton area, I can only tell you that if you've evacuated or know someone who has, you've done the right thing. I try to put myself in the shoes of residents who have been evacuated, and I'm sure for many of you this has been a confusing few days - and the confusion continues. Yesterday morning we received official government reports that dam failure seemed imminent, then we were told in a midday press conference that "imminent" was never the case. Yesterday afternoon we saw a dam engineer telling us the excessive vibration was very concerning, and today an engineer from the very same company told us there's been no excessive vibration and he doesn't know why that term was used. We saw one official this morning telling us the reason for the problem is that the rains causing this flooding caught us by surprise as evidenced by the flooding in New Hampshire and Rhode Island. Make no mistake about it - heavy rains were forecasted and no surprise. Flood watches were up for all of New England for several days, heavy rains were forecasted, media coverage was intense if not excessive leading up to the rain, and dam breaks were part of the concern from as much as one week in advance of the heavy rain. Overall, this was probably among the best-advertised flooding events we've ever had in New England history, and just because flooding occurs doesn't mean it was a surprise. But all of this said, the bottom line is we have to cut through the politics involved here and understand that there's great stress on both dams in Taunton right now, and we are in a wait-and-see mode. Regardless of their conflicting reports, I have no questions that the dam engineers are competent in their inspections, and officials will make the best decision possible. We must cut through the political speech - and it's my hope that I can assist you in this by assuring you that if you've followed evacuation orders, you've done the right thing. We should continue to follow these orders until engineers deem the dam safe - if the worst case scenario should occur, a 6 foot flood wave would make it from the dam to downtown in 60 seconds to two minutes and you would not have time to evacuate, so the need is to be safe and smart. This is costing a lot of us a lot of money in Taunton, but it's necessary at this point. The bottom line of why this happened is no surprise and has happened time and again in the past: the dam is old and not at maximum strength, the rains came down hard, and this is the result. But the bottom line is also that we have to trust that our officials would not put lives in danger, and follow their orders and suggestions as given.
For all folks concerned about obtaining flooding insurance: Please reference www.FloodSmart.gov. This is a government site that has existed for a few years with links to information on obtaining flood insurance.
NOW ONTO THE WEATHER...The next in our series of fast-moving and energetic disturbances moving across New England is racing into the six state region Wednesday morning. For Southern New England, the air is relatively dry and no showers are expected with this disturbance, though morning sunshine will play hide and seek by afternoon with increasing clouds, and breezes will increase from the southwest. As you can see in the forecast at left, the combination of a southwest wind and some limited sunshine will warm much of Southern New England back around or over 60 degrees. In Northern New England, we'll be closer to the energetic jet stream disturbance and its associated surface low pressure center, and this means we'll find showers and periods of rain developing Wednesday afternoon and lasting through Wednesday night with a breezy southwest wind turning to the northwest and draining cooler air into the region. While Southern New England stays dry through Wednesday night (except Berkshire County where a few afternoon and evening showers may pop up), Northern New England finds this cooler air changing rain showers over to snow showers early Thursday morning, and many of us in Northern VT, NH and ME will find snow showers Thursday morning. Now worries - no accumulation is expected except perhaps a brief coating on grassy surfaces.
During the day Thursday, winds will be gusty from the northwest as New England is squeezed between the departing area of low pressure and an incoming bubble of fair weather, or high pressure. These northwest winds will carry down drier air from Canada, and snow showers should dry up in Northern New England while Southern New England sees another day of dry and partly sunny weather.
Our protective bubble of high pressure keeps encroaching rains south and west of New England on Friday, as well. These incoming rains will be the product of the very same bundle of atmospheric energy that brought flooding rains and mudslides to Southern California and the Southwestern US the last few days. As this energetic upper level storm center moves slowly into the Ohio Valley, it will push increasing moisture toward New England, and high altitude clouds will increase Friday afternoon and evening.
By Saturday, as high pressure pulls away from New England, clouds will continue to thicken through the day with a push of warm and moist air pulsing northeast ahead of the aforementioned upper level storm. It appears as though rains will spread into New England by Saturday evening, with periodic rain Saturday evening and night. These rains should not be flooding rains - more likely a widespread light to at times moderate rain.
Sunday and Monday's weather are a bit trickier. Here's why: Hurricane Wilma, as of this writing, is moving slowly toward the west-northwest south of Cuba. She went through a period of rapid intensification last night, and went from a tropical storm to a major Category 5 hurricane over 24 hours. This happened thanks to the warm ocean waters she was sitting over, as well as winds aloft that were perfect for intensification. In fact, a hurricane hunter aircraft penetrated the storm's tiny 2 mile wide eye Wednesday morning, and measured a pressure of 882 millibars - making Wilma the strongest hurricane ever to exist in the Atlantic Basin since record-keeping began in the 1800's. It will be nearly impossible for Wilma to maintain this record intensity over her trek north and northeast the next few days, but she certainly may still be a major and damaging hurricane when she makes landfall. At this point, it appears as though the old California storm moving through the nation will turn the winds such that Wilma will blow into the Western Florida coastline - passing over or near Lake Okeechobee Saturday night. By later this weekend, the questions for our own forecast revolve around exactly how Wilma interacts with the upper level storm moving toward us from the west. There are strong signals that at least part if not all of Wilma will be drawn northwestward toward this upper level storm, and this would bring the possibility of another shot of flooding rain and perhaps strong winds to New England sometime late Sunday or more likely early next week. But at this point, it's a potential we have to acknowledge but we also have to understand this all will depend on the timing of each storm center. Time will be needed to see how the atmosphere evolves in this regard.
Technical Discussion: Out By Early Afternoon.
Have a great Hump Day.
Matt
Matt's Technical Meteorological Discussion: Updated Wednesday, October 19 at 2:00 PM
Pacific moisture tap really not linking up on the south side of this energetic vort cutting across NewEng today, so Srn NewEng should stay dry excepting upslope assisted lift of the Berkshires, while Nrn VT/NH/ME sees rain moving in from W to E. Amounts should be fairly light in most spots though duration of precip extends thru Wed Ngt and into Thu AM as winds shift NW and upslope flow sets in across far north. Mountainous terrain of Nrn VT/NH and NW ME should go from rain to snow showers late Wed Ngt and persist thru Thu AM as cold shot of Canadian air teams with upslope flow for adiabatic cooling. Precip amounts are very light but a coating isn't impossible on grassy surfaces.
Thursday as we squeeze between departing low and Canadian high building SE across Great Lakes, and as baroclinic zone tightens while pushing over and south of NewEng with low-level frontogenesis (not necessarily formation so much as strengthening of the low level thermal boundary) winds will gust over 20 mph from the northwest and air should be cooler than MOS even given downsloping flow. Low to mid 50's should cut it most areas, but obviously cooler in higher terrain and esp upslope areas of the north.
Bubble of high pressure building SE across Great Lakes protects NewEng Thu and Fri. Widespread lows in the 30's Thu night as high builds in. Cirrus clouds to increase later Fri as we find ourselves north of precip shield sliding S of New Eng and thru the Mid-Atl where tight baroclinic zone will be located and isentropic lift begins in warm advection ahead of former California upper low over the OH Valley. 12Z NAM has jumped all over precip into Southern NewEng during Saturday - to me it looks like it's too strong too fast given the forecasted tight baroclinic zone to our south and the strongest warm advection being southwest of NewEng to start the day. Additionally, the 500 mb prog doesn't support the seemingly too far east low level circulation. Probably ends up being a day of thickening clouds with rain developing from SW to NE late in the day and toward eve as warm advection and low level speed convergence nudge into NewEng. Not sold on high amounts for Sat as deep warm and moist advection should remain to our west. Saturday night should bring a decent shot of precip as the occlusion and possibly even a weak triple point from the primary low over the Great Lakes winds northeast and shifts the lift into NewEng. Difficult to say at this point how much we're talking about, but amounts of .5-1.0" are my thinking right now.
From Sunday morning through Monday, a tremendously difficult forecast pattern appears - not necessarily because there are a million different solutions (really there are a relatively low number of possible outcomes) but because of how high the stakes are. For instance...
Worst case scenario: After a stalling occluded front which serves as a pathway for Atlantic moisture and a convergence zone for lift in the low levels, a major storm strike on New England of a hurricane in the process of intense extratropical transition, being pulled westward in retrogression as it's pulled into the tremendous upper level low over the Great Lakes, discussed here in Monday's discussion. A storm such as this would be taking one of the worst trajectories possible into NewEng - coming in from the southeast as it wraps into the upper low - and would deliver a blow of tremendously heavy rain with deep Atlantic inflow and at least Cat 1 winds with likely gusts to Cat 2 as it accelerates and pulls in.
Best case scenario: Wilma goes out to our south, occlusion pivots through quickly and Saturday night's rain is heavier than what I mentioned a few paragraphs ago, but the occlusion goes north and heaviest rain falls along or north of the Canadian border while Wilma skirts out.
The forecasted synoptic situation for the period hasn't changed much from Monday's thinking, which isn't necessarily a good thing for NewEng - that is, the upper level low moving thru the Rockies/Central Plains currently will slow and begin to break apart as it enters the OH Valley, with pieces launching across the Mid-Atlantic coastline with a band of rain along the well defined low-level baroclinic zone. Part of the reason for the pieces left behind by this system meandering in the OH valley is that they become lodged under a building shortwave ridging structure that sets up in advance of a tremendous shot of Canadian energy dropping SSE directly from the Arctic circle. At the same time, we find evidence for the theory of holding rain off on Saturday in the strongly confluent flow at 500 mb that sets up over Eastern NY Friday night and Eastern Maine by Saturday night. As this confluent flow pulls away, the thermal zone to our south is allowed to lift northeast and puts us into a rain shield as already mentioned for Saturday night. Also on Saturday night, a lobe of vorticity pivoting around the belly of the old California upper low will be moving east thru the SE US with thunderstorms and Wilma concentrated rainband, while backing winds and helping to keep Wilma moving across Florida and off the SE US coast. It's then that the Canadian vort max and old upper low combine forces and really deepen the new upper low. In fact, from Saturday night to Sunday night, Ensemble means agree on deepening the negative height anomaly from a -200 gpm to a -300 gpm - not only a remarkable negative anomaly for this time of the year, but also a remarkable rate of deepening, which coincides with the anomalously high heights developing north of the upper low, in Canada, and thereby allowing warm advection into the system from the dynamically unstable ridge to the north. One should note, if for nothing else but posterity, that this dynamically unstable ridge was evident during formation of the Perfect Storm of late October 1991 in the merger of Hurricane Grace. The same disparity in static stability existed across the ridge/trof setup, but the obvious differences were two-fold: 1) The Perfect Storm obviously was much farther east, which plays with things like storm strength, etc., upon time of merger, and 2) The trajectory at which Grace was absorbed, resulting in a retrograding upper low that brought a long-duration blow to NewEng as the storm backed into the coastline. This merger would be occurring farther west and Wilma, should she be absorbed, is going to be riding through New England before being pulled into the upper low entirely. That means the potential for less duration, but higher intensity over a larger area. Otherwise, however, the 500 mb maps for an analysis of Oct. 29-31 '91 and the forecasted map of 500 mb heights for Sunday Night/Monday scenario looks eerily similar with regard to the unstable ridge that eventually completely bridges across the top of a rapidly deepening upper low. Synoptically, what this deepening low would act as an atmospheric sink, so to speak, pulling nearby disturbances toward the center. The question quite obviously with regard to this part of the scheme is whether it can effectively include Wilma in it's sink, or if Wilma can ride out just barely to the southeast of the periphery of the upper low. But of concern on a separate but equally important level is the strengthening of winds that will occur in the jet stream flow along the Eastern Seaboard as the meridional flow sets up. And, as anomalously high heights build across Canada, the easterly component to the upper flow that will establish to the east and north of the upper circulation. The reason for concern with these is obvious when one dwells for a moment - rapid meridional flow would mean rapid acceleration of Wilma, and a more easterly component introduces the potential for a north-northwest moving storm upon impact.
With regard to answering the question of whether Wilma becomes caught in the circulation of the upper level low or not, I truly believe - and followed this in my broadcasts - that the most responsible answer is we just don't know. It's quite interesting to see that even the models progging Wilma to keep trucking SE of NewEng have been doing two important things: 1) Wrapping additional weaker vorts ahead of her NW into the circulation, and 2) Trending farther west with Wilma with each run. These are both causes for concern, obviously. But equally important parameters are the 500 mb height field from the Ensembles - which paint confluent flow SE of Nova Scotia. The Atlantic ridge is forecasted to pulse a bit by Monday, but this may be in response to the influx of latent heat release on the east side of Wilma, so the synoptic pattern may favor taking Wilma SE of NewEng and toward the confluent flow. If this confluence shifts farther E in further runs, this will be a cause for concern. But even if the actual tropical center of Wilma should move SE of NewEng, a piece of Wilma saturated with tropical moisture would still be likely to ride west or northwest up the occluded front that will have moved into NewEng Sat Ngt and likely will stay in place under the weakness in the height field between our two interacting systems. But again...I stress that the only real answer on whether Wilma gets sucked it or spit out is "we have to wait and see."
And we will.
Later!
Matt
Welcome to the weather blog! While the web address has changed, the blog will still be the same Monday through Friday discussion - with some improvements! Over the course of the next few weeks and months, you'll find me experimenting and adding new features. Maps, pictures, and other multimedia are enhancements I'm hoping to be able to make as I learn more about how to maximize the new site. Format will be similar to the old version - you'll find a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. If no technical discussion is available when you check in during the morning, check back later as it often comes after the Weather Summary - I try to indicate at the end of the general weather summary when/if a technical discussion is coming. My email is contact@mattnoyes.net. This blog is for you, so I hope you enjoy it! -Matt Noyes
For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net
Matt's Weather Summary:
We are issuing constant updates regarding risk for flooding of Taunton, MA, from potential Whittenton Dam break along Mill River on NECN. Please follow our broadcasts for these updates.
With regard to our regional New England weather, the overall pattern of the jet stream has changed significantly from what it was this past weekend. The jet stream is the fast river of air aloft in the atmosphere that steers our storm systems and acts as a thermostat, separating cool air to the north, from warmer air to the south, and for most of last week, these winds were siphoning warm and moist air aloft from the Tropical Atlantic into New England. The recent shift in the jet stream winds has brough a pattern that flows from Northwestern Canada to New England - which keeps energetic but fast moving storm centers diving across New England through the week, each delivering a shot of slightly cooler air but none through Saturday delivering anywhere near the amount of rain we saw this past weekend.
The first fast-moving jet stream disturbance to affect us brought showers to New England this morning. As it continues its push eastward, it will help to kick out the large storm east of Maine that brought the widespread heavy weekend rain and gusty winds to begin the week. As this new disturbance moves east and pulls its attendant showers north and east - settling across Northern New England with clouds and a few showers through Tuesday afternoon - drier air bringing sunshine to the Southern Tier of New York Tuesday morning will continue to move east and break the clouds for midday and afternoon sunshine in much of Southern New England from west to east. West to southwest winds will gust over 20 mph in most of Southern New England, bringing a breezy day and helping to usher in the somewhat warmer air.
Wednesday begins with milky sunshine through high-altitude cirrus clouds after a cool and quiet night Tuesday night, but yet another disturbance at the jet stream level will be swooping in from Canada, caught in the fast winds aloft. This means clouds should increase yet again during the day on Wednesday. This time, however, it appears as though there won't be much moisture to squeeze out in Southern New England, and right now I'm thinking most of the showers will fall across Northern New England late Wednesday through Wednesday night. With this disturbance dragging a cold front through New England at the surface...enough cold air should be in place by late Wednesday night into Thursday morning for snow to fall in Northern New England - from Northern Vermont into Central and Northern Maine, and probably not just in the moutaintops, but at our bases as well! At this point, it's not looking too significant - just a sure sign that winter's not far away.
For the rest of us, the passage of Wednesday Night's cold front may be mostly dry, but it still marks the leading edge to a reinforcing shot of cool air that will bring breezy and brisk conditions on Thursday. In this fast flow of weather disturbances, clouds will thicken again later Friday with rain showers possible Friday night into Saturday, then a steadier rain on Sunday or Monday as another jet stream disturbance and the associated surface low pressure center move through. The concern for this storm center, is the possibility that a piece of Tropical Storm Wilma - currently south of Cuba and steadily strengthening - may become involved in the storm center, and another heavy rain event may be on the way for late this weekend or early next week. It's still early, though, and I don't like the idea of rain on my weekend anymore than you do, so let's give it time and see what happens.
Technical Discussion: Yesterday's was posted late because it was so long - took me awhile to write! I'll freshen it up, and if I have time I'll add more at the top later today, but my synoptic thinking hasn't changed so for now please reference yesterday's technical discussion found in the archives at left.
Have a wonderful day.
Matt
Matt's Technical Meteorological Discussion: Updated Tuesday, October 18 at 2:00 PM
A freshened up re-post of yesterday since many of you missed it due to the late post.
Transition to fast flow is underway as upper low east of Maine will pull east and decay while broad weestern ridge/eastern trough pattern sets up across the northern tier of the US. Caught in the fast jet stream flow will be multiple energetic shortwaves that will dive SE across NewEng the next several days, with the amount and intensity of precip they produce dependent largely on available low-level moisture. This broad northeast troughing will persist until the middle to end of the last week of October as lower heights are left in the wake of the current large cyclone and serve as a sink for shortwaves ejecting east from the monster energy diving over and S of Alaska to create a rather intense Aleutian low. While 500 mb heights will remain anomalously high over Northern and Central Canada, effects of the season are enough to result in building cold air across the higher latitudes. Therefore, as energy ejects east and then southeast across Canada heading for NewEng, it will bring with it installments of cool air through the end of October. Thereafter, signs are for the Aleutian low to weaken but remain intact, keeping ridging across the Intermountain region and weak troughing in the Northeast. But the cold shots over the next two weeks may largely exhaust what's available for cold air in Central Canada, and with high heights in that region, warmth building across the western US may morph into a larger scale near to above normal temperature regime for the US, with the Northeast on the outer fringes and still subject to modified cool shots with our weak persisting trough.
Those are my thoughts on the overall longwave pattern.
Tuesday intense vort and crashing heights cross NewEng. Increased instability with cooling aloft means plenty of clouds thru the day most spots, tho drying aloft works in behind the vort late and some parts of Srn NewEng break clouds to sun. SW wind tries to advect surface warmth but with most of NewEng hard pressed for sunshine, temps will not be eager to rise. Based on forecast of sunshine breaking thru late, we can get 60's Southern NewEng, but 40's and 50's north under day-long clouds North. Most areas of NewEng see showers with period of greatest dynamic forcing and cyclonic vorticity advection from mid-morning thru early to mid-afternoon.
Morning sunshine mixes atmosphere to bring temps back near 60 on average for Wednesday, but I'm not buying widespread mid 60's MOS guidance is touting just yet. Too much chill comes in behind Tuesday's shortwave to retreat it so quickly even with warm advection ahead of Wednesday night's shortwave. My initial thinking was that, without much moisture available, we may even see a dry frontal passage in Southern NewEng but I'm reconsidering give 850 Theta-E shows plume of moisture straight out of the Pacific comes across Plains and OH Valley and interacts with front. This moist tongue may penetrate far enough northeast to produce precip. Farther north, enough energy for strong forcing to crank out rain showers that will change to snow showers later Wednesday night into Thu AM along the Canadian border. Thursday morning an extended period of snow showers is likely in Northern NewEng with the combination of a shot of cool air to the tune of -6 C at 850 mb and upslope flow. Otherwise, downsloping combined with drying brings the sun back out in Southern NewEng and along the coastal plain.
Looks like sun's back on Fri AM, but next in the line of shortwaves is ready to truck into NewEng Friday night into Sat - so clouds increase late Fri and rain develops Fri Ngt and lasts off and on thru Sat. This may not be the innocuous shower event it appears to be at first glance - this energy is the remnant of the UL low over Southern CA today, and will feed off of it's own moisture that it's currently pumping in from the Pacific. With such a fast and active flow in the Northern stream, there is every opportunity for this Southern stream low to merge with one of the energetic shortwaves embedded in the northern flow. In fact, multiple Ensemble members are picking up on this possibility and cranking out a heavy rain event for most of NewEng Saturday into Sunday as ridging amplifies over the Rockies. This amplification relates back to the strengthening Aleutian low mentioned at the start of this discussion - with an amplified Eastern Pacific trof, the Rockies ridge has no choice but to amplify in response. Following this longwave pattern, this favors a pulse deepening of the SE Canada/Ern US trof, which will allow for yet another storm to crank up vicinity NE US. Canadian Ensembles also keying in on this potential and are likely significantly underforecasting potential QPF amounts at this early juncture, marking the axis of heaviest precip from SE NY to Nrn ME with .50", but right now I'd throw that amount away, because this will either be a non-event, or a heavy QPF event and I think we're only seeing the beginning of what will be a wet and wild trend.
Part of the reason for this expected trend is that we, of course, we have Wilma to contend with, and perhaps not just Wilma. Given time constraints, I will bypass a complete tropical discussion on Wilma and the other tropical features, but we have two areas of disturbed weather that I'm most interested in over the Tropical Atlantic - one northeast of Puerto Rico and the other east of the Leeward Islands. As for Wilma, even if she passes over Honduras and is degraded - which I'm not sure will be the case given that her center lay to the north of the deep convection - while she would be torn apart she would come back over the still-warm waters of the Gulf of Mexico, and a strike on the Northern Gulf coast...at this point...seems like a pretty decent solution given the repetitive shortwaves diving into the Lower MS Valley by this weekend with the only-just-begun-to-amplify trough (just getting going Saturday). Additionally, the ridge holding firm over the Central Atlantic will not allow the circulations mentioned above to move northward and away from the US - they have two choices this week by the Leeward Islands: 1) Decay and become a non-player, 2) Move westward. At least one of these circulations should move west and hold together, if not both, though they may have different compositions, as the circulation northeast of the islands currently is non-tropical aloft and only now trying to spin up deeper convection from time to time and failing. This upper low looks unfavorable to become tropical right now, though it has an extremely important role in enhancing outflow on the northeast side of Wilma, which is so impressive it's resulting in convective bands removed well NW of her center. There are two waves located east of the Leeward Islands that are moving west, and indications are that as the leading wave encounters the upper low mentioned above, it will slow and the second wave will be the feature of concern. Though by the time this feature moves far enough west to become a player it may be too late...then again, it may not.
Too late for what? As mentioned above, Wilma looks like eventually she is going to have to come north with a weakness developing in the ridge north and northwest of her. The problem is that as she starts to come north the trough deepening explained above is already underway from the Great Lakes to the northeast. Remember what we've reviewed in these discussions in the past - deepening upper lows will serve as a sink when the pattern becomes amplified. The concern here is that the developing upper low becomes a sink ready to pull Wilma - and perhaps the additional wave east of the Leeward Islands - north/northeast and northwest, respectively. Whether this all happens at once, or one piece at a time it is too early to say, but one would have to think whatever is left of Wilma is not going to be able to ride due north over or west of the Appalachians with the height falls that will be occurring over the Ern US, and instead will have to come north to the Gulf coast, hook northeast, then would feel the effects of the Northeast upper level sink, perhaps pulling the aforementioned wave in as she curls around or over the Southeastern US.
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