MATTNOYES.NET - Weather Website & Blog

SPECIAL FEATURE: TROPICAL ATLANTIC STORM FREQUENCY A DIRECT LINK TO CLIMATE CHANGE?

The following story, pasted below, appeared on most news organizations Monday, July 30.  The premise of the article is a summary of a recent study in which "researchers" believe they've determined not only that the frequency of Atlantic tropical storm activity increased in steps, but furthermore that there is a direct link to human-induced climate change.  Some experts are calling this "sloppy science" while others are commenting on the validity of the study.  So what is my take on this, and how should we view this study as meteorologically interested and informed individuals?

SPECIAL FEATURE: TROPICAL ATLANTIC STORM FREQUENCY A DIRECT LINK TO CLIMATE CHANGE?

The following story, pasted below, appeared on most news organizations Monday, July 30.  The premise of the article is a summary of a recent study in which "researchers" believe they've determined not only that the frequency of Atlantic tropical storm activity increased in steps, but furthermore that there is a direct link to human-induced climate change.  Some experts are calling this "sloppy science" while others are commenting on the validity of the study.  So what is my take on this, and how should we view this study as meteorologically interested and informed individuals?

EARLY DENSE FOG YIELDS TO SUNSHINE...SUMMERY WEEK AHEAD

Welcome to the weather blog - a regular Monday through Friday discussion of the weather!  While the discussions usually will only come on days I'm working, I'll issue special updates when the weather warrants.  I will always post to let you know when no discussion is expected if I'm away on vacation, etc. - if no update is here and no info is available, that likely means the server has temporarily gone on the fritz and I will update as soon as technically possible.  You'll find a quick weather synopsis linked to the daily forecast at the top of the page, a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow by mid-afternoon. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

General Weather Summary:

NEW EXCITING FEATURE!  Thanks to the folks at answers.com, you can now double click on just about any word in my discussions to find out what a term means - no more trying to guess what weather terms mean!  If there's a word you don't know, double click on it, and chances are good you'll get a description.  This is a phenomenal learning tool for those who take an interest in weather, or who simply want to gain a more complete understanding of the forecast, and works best using Internet Explorer.  Please note that the page must be loaded completely for this feature to work, and a "refresh" can assist if the feature is sluggish.

The same stalled front that has been dividing two airmasses across New England will waver over the Southern half of the six-state region Tuesday, gradually settling southward and allowing slightly less humid and slightly cooler air to move into even southern areas by Tuesday evening.  Meanwhile, Tropical Storm Chantal has developed in the waters east of New England, but will have very little impact on the area.

For now, the same pesky stalled front - called a "stationary front" - not only defined the line between drier air to the north and more humid air to the south, but also focused moisture into very dense fog near this boundary early Tuesday morning, with some of the most widespread dense fog the Boston Metropolitan area has seen in quite some time!  This fog, though lifting into a deck of low altitude gray clouds before burning off, was rather shallow, and as the fog and resultant cloud deck burns off, sunshine will take control of our Tuesday regionwide.  Though the air seeping southward across New England may be somewhat less humid, the onset of this air isn't much cooler, as high temperatures on Monday reached the middle 80s across the Canadian border, and sunshine will warm the air into the 80s and even close to 90 in some parts of Central and Southern New England Tuesday afternoon.  With a small bubble of high pressure near New York City, and the clockwise flow of air around the high pressure cell, a north wind will prevail for most communities, but will remain quite light through Tuesday afternoon, swinging around to a bit of a sea breeze in favored coastal locales.  With a relatively light wind and warm waters over Vineyard and Nantucket Sound, even the islands of Massachusetts will bask in warmth Tuesday afternoon.

Overnight Tuesday night, light wind and partly cloudy skies will combine for cooling temperatures into the 50s and 60s north, and 60s to around 70 central and south.  Though the air will be drier than previous nights, temperatures will likely cool enough for dense valley fog to develop.  The remainder of the week will keep this same pesky front closeby, settling southward into far Southern New England for a time on Wednesday as somewhat cooler and slightly less humid air takes hold amidst plenty of sunshine, then riding northward again on Thursday with a return of deeper heat and humidity, but enough dry air aloft to preclude any shower development.  By Friday, a faster moving weather pattern will be taking hold, and a new upper level disturbance will be moving from west to east across the Great Lakes and toward New England.  While this represents available energy aloft, it also will be dragging and associated cold front at the surface, likely to bring showers and thunder later Friday afternoon and evening.

Though there is still question regarding how quickly the associated front passes through New England heading into the weekend, it's likely that this front will by and large clear New England early Saturday, taking any lingering Friday night rain and Saturday morning clouds southward with it, and allowing a slice of cooler and drier air to settle in gradually late Saturday and Sunday, yielding an enjoyable weekend regionwide.  The weather is likely to turn decidedly more unsettled heading into the beginning of next week, though, as warmth and humidity rides northward into New England again, accompanied by a fast jet stream flow of numerous energetic disturbances aloft that may result in periodic rounds of showers and thunderstorms through the beginning of next work week.  Though unlikely to result in a string of washed out days, certainly it would appear as though at least a chance of showers and thunder would be present each day early in the week.

In the Tropical Atlantic, the cluster of thunderstorms mentioned here in yesterday's discussion near Bermuda was classified as Tropical Depression #3 overnight Monday night between Bermuda and Cape Cod, then strengthened to Tropical Storm Chantal early Tuesday morning as it heads north-northeast, perhaps brushing Eastern Nova Scotia on its way into the North Atlantic, and generating 15-20 foot seas in the Grand Banks, while New England waters see very little swell from the storm, owing to its rapid northeast motion and its development so far north.  Other areas of disturbed weather in the Tropical Atlantic include an area of persistent thunderstorms near the Windward Islands associated with a tropical wave that has some potential for growth as it moves slowly west-northwest in the coming days.  Thunderstorms off the Carolina coastline occasionally show signs of organization but do not appear tropical in structure, and though there are signs that significant thunderstorms may develop in place over the Northern Gulf of Mexico waters in the coming days before crossing the Southeast, there are no signs of immediate development.

Matt

TUESDAY PODCAST: EARLY DENSE FOG YIELDS TO SUNSHINE...SUMMERY WEEK AHEAD

The Quick Weather Synopsis is now a Podcast!  You can either click on the audio controls above the forecast on the main homepage, or to subscribe to the Monday-Friday podcast (updated on all days I'm working):

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SLOW MOVING THUNDERSTORMS TO BRING LOCALIZED FLASH FLOODING...IMPROVING CONDITIONS THROUGH THE WEEK

Welcome to the weather blog - a regular Monday through Friday discussion of the weather!  While the discussions usually will only come on days I'm working, I'll issue special updates when the weather warrants.  I will always post to let you know when no discussion is expected if I'm away on vacation, etc. - if no update is here and no info is available, that likely means the server has temporarily gone on the fritz and I will update as soon as technically possible.  You'll find a quick weather synopsis linked to the daily forecast at the top of the page, a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow by mid-afternoon. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

General Weather Summary:

NEW EXCITING FEATURE!  Thanks to the folks at answers.com, you can now double click on just about any word in my discussions to find out what a term means - no more trying to guess what weather terms mean!  If there's a word you don't know, double click on it, and chances are good you'll get a description.  This is a phenomenal learning tool for those who take an interest in weather, or who simply want to gain a more complete understanding of the forecast, and works best using Internet Explorer.  Please note that the page must be loaded completely for this feature to work, and a "refresh" can assist if the feature is sluggish.

Slow moving thunderstorms are developing across New England near a front that's stalled out through eastern and central New England.  Though this front represents the boundary between warm and humid air with drier and cooler air, the dividing line is not well-defined, and a transition to drier air will be gradual.

For now, following one large area of rain and thunder that moved through the Boston Metropolitan area early Monday morning, new downpours and thunderstorms are developing.  While the best way to follow these storms is through radar imagery, linked to the right of this discussion, there are some governing factors that will determine where the greatest threat for flooding exists.  For example, with a stationary front - a stalled boundary between cool and dry air to the north and warm, humid air the south - stalled over Eastern and Southern New England, the most coverage of thunderstorms Monday afternoon will be through Central, Eastern and Southern New England, from Bangor, Maine, southwest through Portland and Augusta, Portsmouth, Concord and Manchester, Keene to Springfield, MA, and Hartford, Providence, Boston and Worcester.  Farther north and west, sunshine will create a wonderful summer afternoon, though in the areas of storms, any of these storms that develop will not only be fueled by ample humidity and driven by a slow moving energetic disturbance aloft, but also will be very slow to move, owing to lax winds aloft.  With very little wind to push storms, communities that are under these storms will see rain falling at a rate of one to two inches per hour for perhaps three hours or more in some of the unluckier cities and towns!  This amount of rain in such a short period of time raises concerns for localized urban flooding, street flooding and stream/small river flooding.  Individuals near streams and small rivers who experience prolonged heavy rain should monitor the link at left for Active Watches/Warnings/Advisories or utilize the Weather Bug tool by entering your zip code.

Areas of heavy rain and thunder will only gradually wane Monday evening, but by Monday night only scattered showers will remain.  With light wind continuing overnight, areas of dense fog will develop in the more humid central and southern New England regions, while the drier air in place across the North Country will actually allow temperatures to fall into the 50s and perhaps even 40s in a few northern valleys!  Though that Canadian air is substantially cooler and drier, that doesn't mean its progression southward will be any quicker, and as the installment of slightly more comfortable air eases southward Tuesday afternoon, a few scattered thunderstorms are likely, especially in Central and Northern New England.  Otherwise, however, sunshine will burn through morning fog and low altitude clouds, so a relatively nice Tuesday is expected amidst any scattered showers and storms later in the day.

The remainder of the week will keep this same pesky front closeby, settling southward into far Southern New England for a time on Wednesday, then riding northward again on Thursday.  All the while, though, while surface humidity and moisture in the lowest few thousand feet of the atmosphere will still be sufficient for a bit of a sticky feel and bubbling puffy cumulus clouds, drier air several thousand feel above our heads will limit the chance of precipitation, leaving two mostly dry days of wavering temperatures.  By Friday, a faster moving weather pattern will be taking hold, and a new upper level disturbance will be moving from west to east across the Great Lakes and toward New England.  While this represents available energy aloft, it also will be dragging and associated cold front at the surface, likely to bring showers and thunder later Friday afternoon and evening.

Though there is still question regarding how quickly the associated front passes through New England - if at all - heading into the weekend, it's likely that we'd find a break in the action between energetic disturbances, meaning that right now scattered showers and thunder would appear to be worst case scenario for Saturday and Sunday, with a great weekend in the cards - at least right now.

In the Tropical Atlantic, there are two disturbed areas to watch - one that is south of Bermuda and may be classified as a "Subtropical storm" (not quite tropical, but close enough to be named as one) if it can hold thunderstorms around its center, though so far that has failed to happen, and another disturbance by the Windward Islands, northeast of South America, that holds potential for tropical development but not for another couple of days, most likely.

Also, there was an interesting study about the Tropical Atlantic and an asserted tie to global climate change.  I'll address this in another post to follow later this afternoon.

Matt

MONDAY PODCAST: SLOW MOVING THUNDERSTORMS TO BRING LOCALIZED FLASH FLOODING...IMPROVING CONDITIONS THROUGH THE WEEK

The Quick Weather Synopsis is now a Podcast!  You can either click on the audio controls above the forecast on the main homepage, or to subscribe to the Monday-Friday podcast (updated on all days I'm working):

Easiest way is to subscribe by clicking here!

Or, you can open ITunes.  Under "Advanced," select "Subscribe to Podcast." For the URL, copy and paste this: http://www.mattnoyes.net/matt_noyes_weather_blog/rss.xml

You can also use the "Subscribe to Podcast" link in the upper left corner of the main page.

The daily file you will receive is Daily_Weather_Synopsis.mp3

FRIDAY PODCAST: THOUGH AN UNSETTLED WEEKEND LAY AHEAD, MOST WILL GET PLANS OFF WITHOUT A HITCH

The Quick Weather Synopsis is now a Podcast!  You can either click on the audio controls above the forecast on the main homepage, or to subscribe to the Monday-Friday podcast (updated on all days I'm working):

Easiest way is to subscribe by clicking here!

Or, you can open ITunes.  Under "Advanced," select "Subscribe to Podcast." For the URL, copy and paste this: http://www.mattnoyes.net/matt_noyes_weather_blog/rss.xml

You can also use the "Subscribe to Podcast" link in the upper left corner of the main page.

The daily file you will receive is Daily_Weather_Synopsis.mp3

THURSDAY PODCAST: AS HUMID TROPICAL AIR BUILDS, CHANCES FOR THUNDERSTORMS INCREASE THROUGH THE WEEKEND...CAREFULLY WATCHING EARLY NEXT WEEK

The Quick Weather Synopsis is now a Podcast!  You can either click on the audio controls above the forecast on the main homepage, or to subscribe to the Monday-Friday podcast (updated on all days I'm working):

Easiest way is to subscribe by clicking here!

Or, you can open ITunes.  Under "Advanced," select "Subscribe to Podcast." For the URL, copy and paste this: http://www.mattnoyes.net/matt_noyes_weather_blog/rss.xml

You can also use the "Subscribe to Podcast" link in the upper left corner of the main page.

The daily file you will receive is Daily_Weather_Synopsis.mp3

WARM SUMMER DAY LEADS NEW ENGLAND INTO MUGGY STRETCH TO END THE WEEK

Welcome to the weather blog - a regular Monday through Friday discussion of the weather!  While the discussions usually will only come on days I'm working, I'll issue special updates when the weather warrants.  I will always post to let you know when no discussion is expected if I'm away on vacation, etc. - if no update is here and no info is available, that likely means the server has temporarily gone on the fritz and I will update as soon as technically possible.  You'll find a quick weather synopsis linked to the daily forecast at the top of the page, a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow by mid-afternoon. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

General Weather Summary:

NEW EXCITING FEATURE!  Thanks to the folks at answers.com, you can now double click on just about any word in my discussions to find out what a term means - no more trying to guess what weather terms mean!  If there's a word you don't know, double click on it, and chances are good you'll get a description.  This is a phenomenal learning tool for those who take an interest in weather, or who simply want to gain a more complete understanding of the forecast, and works best using Internet Explorer.  Please note that the page must be loaded completely for this feature to work, and a "refresh" can assist if the feature is sluggish.

Please Note:  I'll be off Thursday and Friday, so this discussion will stand through the weekend.  As you'll read, though, I'm still very much uneasy with the forecast for early next week, so while a full discussion won't be out in the next few days, I'll update with some thoughts on early next week as the picture becomes clearer.

Weatherwise, Wednesday will bring a truly fantastic summer day regionwide as the heat cranks up a notch while humidity levels lag behind slightly.  The remainder of the week, however, will bring an increasingly muggy feeling with at least scattered showers and thunderstorms entering the forecast.

Morning fog in our valleys Wednesday morning lifted into a layer of low altitude clouds that quickly burn off, leaving behind mostly sunny skies for the balance of the day.  All the while, the nearly stationary upper level storm to our west, over Western Pennsylvania, will continue to spin counter-clockwise, rotating bands of clouds, rain and cool air around its pinwheeling center and over parts of Pennsylvania, New York, Ohio and the Virginias.  In New England, we're far enough removed from that storm that we'll have no concerns with its direct effects on our weather, though the deep nature of this storm - stacked from a weak low pressure system at the surface to a steady and strong circulation aloft - will maintain a fairly deep south wind through the atmosphere, which means we'll load heat and humidity gradually into New England.

With the feed of humid air remaining slow into New England, Wednesday will be a bit more humid than Tuesday, but not all that sticky by New England standards.  Therefore, Wednesday will likely end up the most comfortable of the summery days this week, with enough warm air in place to boost temperatures to either side of 90 for all communities from Northern Maine to Southern Connecticut, and everywhere in between, excepting Cape Cod and the Islands where temperatures will still come into the 80s - very warm by island standards!  The remainder of our New England coastlines will wait until late afternoon for any sea breeze to develop, and though temperatures may fall near the coastline in response, that will only be after temperatures max out near 90 for seaside communities, too.

The light flow of southwest wind will continue Wednesday night, meaning temperatures will remain mild as noticeably more humid air moves in, and sleepers find some additional discomfort over the past nights, with valley fog once again a possibility for deeper valley communities.  Much like Wednesday morning, Thursday will see lifting and then dissipating fog, with temperatures rebounding into the lower 90s in Southern New England, and around 90 elsewhere.  Dewpoint temperatures - the measure of the amount of moisture in the air - will continue to creep up, with a stickier feel taking hold, but with a nearly due south flow through the atmosphere, there will be little in the way of atmospheric pollution, and therefore little in the way of haze.  In fact, observations with this incoming airmass featured unlimited visibility on Wednesday and I expect to find very little obstruction to visibility here at home on Thursday.  Still, the building moisture in the atmosphere will also provide fuel for thunderstorms, and the biggest question will revolve around whether there is a strong enough disturbance moving through to touch off any thunderstorms.  Though it, admittedly, wouldn't take much to bubble up a storm, there also won't be much to work with, with a rather quiet flow through the atmosphere.  There is, however, one disturbance over the Northern Gulf of Mexico, believe it or not, that will be caught in the jet stream flow aloft, and will zip northward in our deep and fast south wind high in the sky.  That disturbance, when it moves through Thursday afternoon, may touch off an isolated thunderstorm in the Pioneer Valley, though the remainder of New England should remain dry again.

A muggy and uncomfortable Thursday night will yield to another day of heat on Friday.  To our west, the upper level storm over Ohio and Pennsylvania will slowly break down over the end of the workweek, breaking into pieces as a lingering bundle of energy drifts northeast while weakening.  The slow progression of this disturbance through the weekend will mean a few things for New England - 1) the warm and muggy air will stay in place through Sunday, 2) a cold front, the leading edge to cooler and drier Canadian air, will have to wait until the upper level disturbance pushes through before it can settle south across New England, and 3) The chance for thunderstorms will increase each day until that disturbance has passed.  This means a better chance of thunderstorms bubbling up Friday afternoon, primarily through interior New England, as temperatures soar into the lower 90s in many spots again.

The slow northeast drift of the upper level energy center this weekend, and the approach of the cold front at the surface from Canada, will focus numerous downpours and thunderstorms Saturday and Sunday.  On both days, any of these storms should contain very heavy rain (the atmosphere is packed full of moisture) and frequent lightning, but some storms are quite likely to contain strong damaging wind, as well.  On Saturday, most of the focus for storm development will lay closest to the combination of upper level energy and the approaching cold front, meaning Northern and Western New England will see the most storm coverage, with scattered storms farther south in Central New England (mostly later in the day as the northern and western storms develop farther southeast) and few if any storms in Southern New England.  Saturday night will probably see at least scattered thunder and downpours floating around New England - especially Central and North - and the sluggish surface cold front will interact with the equally slow upper level disturbance to create numerous midday and afternoon thunderstorms across most of New England on Sunday.  Though it won't rain all day long, these storms once again will bring heavy rain to the communities they hit.

By early next week, indications are that the upper level ridge - or fair weather center - off the Atlantic Seaboard simply won't want to give way, meaning our upper level disturbance nearby will have little room for escape.  What is left to determine, therefore, is whether the disturbance can beat down the northern side of this Atlantic high pressure before it falls apart completely.  The reason that battle is so important to next week's forecast, is because it may literally represent the difference between flooding rain and gorgeous weather...seriously!  Think of it this way: a deep flow of winds from the south is bringing humidity and warmth into New England directly from the Gulf of Mexico and Tropical Atlantic.  This week, we're fortunate that no major disturbances or really heavy moisture is available, so the flow of tropical air is relatively transparent.  Next week, though, there will be several disturbances, especially at the start of the week, that will be loaded with Gulf moisture.  If this weekend's disturbance can beat down the edge of the Atlantic high pressure center, we deflect the steady tropical flow to our south, and end up in cooler, drier Canadian air.  If it fails to deflect the wind, each of those disturbances rides north and brings heavy rain to New England.  As of this writing, I can tell you the bulk of the projections favor moving drier air into the Northeast and keeping the rain south, but the Atlantic high pressure is building, and a recent trend in our guidance has been to keep the flow of moisture and rain over New England early next week.  This will bear watching in the coming days.

Here's to a great weekend - will update on early next week at some point.

Technical Discussion:  Probably not today.  I'm off the next few days and time to update will be limited, but perhaps at some point in the next few days I'll be able to bang one out.

Matt

Matt's Technical Meteorological Discussion: Updated Monday, July 23 at 2:05 PM

In typical NewEng fashion, as the clouds and cool air remain locked in for most, Nantucket has broken out into beautiful sunshine and the Cape may soon follow.  It appears this is the result of the tropical air infusing extreme SE areas, and this poses the question of how cloud cover is going to play out on Tuesday.  For now, clouds will continue to thicken N after a great day while complex setup takes shape. Positive theta-e advection today is progressing north at 850 and 700 mb, and will be followed by sharply negative theta-e advection overnight Monday night into Tuesday.  This is mirrored aloft and skies clear above about 900 mb.  Beneath that, however, the concern focuses upon inversion strength on Tuesday, as boundary layer will remain quite moist Mon Ngt and this is likely to lead to lots of clouds and areas of fog Mon Ngt into Tue AM, with scattered light showers still a possibility Mon Ngt given moisture and vorticity lobe rotating through.  With presence of inversion Tue AM, mixing will be dependent upon kicking up wind, and winds should be quite light with dying sfc low reflection riding overhead.  Where winds increase a bit...and where relative humidity is lower...we should find sun breaking through, and this includes far Southern NewEng and far Northern NewEng, respectively.  Elsewhere, unless the winds can kick up more than expected either at the surface or 850 mb, it'll be tough to get more than just breaks of sun between lots of clouds.

This should turn around very quickly Wed with good mixing, increased wind field and with tropical air in place temps should come up quickly.  Tropical cumulus will pop Wed, Thu and Fri with a weak shortwave streaming north out of the Gulf of Mexico and up the Eastern Seaboard touching off isolated thunder Wednesday.  Appears as though we may find a break in the action on Thu between shortwaves and therefore at this point I'm carrying a dry day, tho certainly timing of shortwaves can change this and I'm also aware that at least an isolated to widely scattered storm would be possible regardless, given abundant ambient relative humidity, and even though ridge is building over us, one would think the deep southerly flow implies enough tropical moisture is present to boost CAPE high enough to overcome any weak capping.  But, again, with no obvious trigger at this point, figured a drier forecast is best representative of NewEng and will re-evaluate tomorrow.

Fri and Sat should bring numerous convective cells with organization owing to strong shortwave and then surface front pushing southward.  Of course, all the while, upper low to our west is prohibiting the significant warmup that I finally thought might be for real at the end of this week.  Yes, ridging builds over us, but this sets up a deep tropical flow from the south, which is humid and warm deep through the atmosphere but not a chunk of the searing Western heat, and with another northern shot trying to intrude by Sunday, one has to wonder what our chances are of getting any of this warmth, or whether this upper low permanently sends the deep warmth sailing into Canada. That's something I'll try to look at here later in the week.

Matt

WEDNESDAY PODCAST: WARM SUMMER DAY LEADS NEW ENGLAND INTO MUGGY STRETCH TO END THE WEEK

The Quick Weather Synopsis is now a Podcast!  You can either click on the audio controls above the forecast on the main homepage, or to subscribe to the Monday-Friday podcast (updated on all days I'm working):

Easiest way is to subscribe by clicking here!

Or, you can open ITunes.  Under "Advanced," select "Subscribe to Podcast." For the URL, copy and paste this: http://www.mattnoyes.net/matt_noyes_weather_blog/rss.xml

You can also use the "Subscribe to Podcast" link in the upper left corner of the main page.

The daily file you will receive is Daily_Weather_Synopsis.mp3