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:
Deep summer heat and humidity is streaming into New England today, and will take up residence here through midweek, before another shot of cool and comfortable air displaces the taste of summer.
In the meantime, a band of broken clouds has been signifying the leading edge to the deep warmth as it's been progressing slowly but steadily northeast across Northeastern New England. Under these clouds, morning showers evaporated but will likely redevelop as scattered afternoon showers and thunder, instigated by the boundary between slowly departing comfortable air leftover from the weekend and incoming heat, haze and humidity, and traveling from northwest to southeast, steered by the jet stream winds aloft that are diving across New England. South of the jet stream and south of the band of clouds, warmer air is taking hold, and temperatures are easily climbing into the middle and upper 80s Monday afternoon, but these areas of Central and Southern New England are far enough removed from the jet stream winds to avoid disturbances aloft, likely staying dry through Monday. As the jet stream winds continue to lift gradually northeast Monday night, another upper level disturbance will touch off showers and thunder for Northern Maine, while the remainder of New England finds mild and muggy conditions with low temperatures either side of 70! This sticky night will likely mean air conditions will switch on across New England, unlikely to rest until the soupy air is swept away Thursday night.
Between now and then, the weather setup features a building high pressure center off the East Coast, centered near the island of Bermuda and therefore referred to as a "Bermuda High." These high pressure cells historically provide the warmest air to New England as the clockwise flow of air around their center promotes a southwest flow of wind into New England, carrying deep summer warmth out of the nation's Midsection and into the Northeast. This southwest wind, after being active on Monday, will continue to blow lightly Monday night, ushering in higher dewpoint temperatures. Remember that dewpoint can be used as a measure of the amount of moisture in the airmass, and the higher the dewpoint, the more humid our air is - dewpoints in the 50s typically are comfortable, in the 60s is typicallly sticky, and above 70 degree dewpoints usually brings an oppressively humid feeling. Of course, this also means plenty of moisture is packed into the atmosphere, and therefore areas of fog are possible Monday night. All the while, though, an increasingly humid feeling will make overnights all that much more uncomfortable for New Englanders beginning Monday night and lasting until the passage of a cold front Thursday evening!
Though lots of moisture in the atmosphere normally breeds numerous thunderstorms, Tuesday is unlikely to yield many if any showers and storms. Even as temperatures soar into the 90s, the air aloft will be quite warm (not favorable for thunderstorms) and more importantly, there will be very little impetus for deep cloud growth. For this reason, I'm expecting a dry Tuesday with the possible exception of Northern Maine, closer to the jet stream winds funneling disturbances across Southern Canada. Otherwise, after another uncomfortably warm and sticky night Tuesday night, temperatures will climb into the 90s again on Wednesday.
Indications are that Wednesday's airmass may be even hotter than Tuesday, allowing temperatures to climb into the middle or perhaps even upper 90s, especially in Eastern New England where "downslope flow" will aid in warming the atmosphere. Those who read regularly will remember that "downslope flow" is the flow of air when the wind blows that air over a hill or mountain, and it comes sloping down the other side of the terrain. Upon descent, the air encounters increasing atmospheric pressure, and is warmed/dried on its journey. A west-southwest wind would be the perfect direction for warming air Wednesday afternoon east of the Worcester Hills, White Mountains and Green Mountains. The difference between Tuesday and Wednesday, however, is that Wednesday will bring a jet stream disturbance directly over New England during the afternoon, and this will spark scattered thunderstorms. With so much heat and humidity packed into the atmosphere, it won't be hard to create severe (damaging) thunderstorms with strong damaging wind, and of course a combination of heavy rain and frequent lightning. Given the warmth of the atmosphere, hail is less likely to be a widespread concern but certainly could still result in the stronger thunderstorms. These storms would persist into Wednesday evening, and scattered storms would last through the overnight in Northern New England Wednesday night, in advance of a southward sagging cold front settling into the North Country from Southern Canada.
It's the same front that brings showers and storms to the North Wednesday night that will bring a day of scattered showers and thunder to most of New England on Thursday. Because of the slow speed at which the front will move through, a humid airmass is likely to persist through the day on Thursday as temperatures climb into the 80s even with more clouds than sun. The front will be marked by a wind shift and an accompanying round of thunder, which will herald in much drier, much more comfortable air for Friday. That fantastic feeling air is likely to remain with New Englanders through the upcoming weekend, as a chunk of below normal temperatures settles overhead for Friday through Sunday!
Thereafter, we have exhausted our chance of much above normal temperatures, at least for now. Instead, I would expect temperatures to run below normal for the first 10 days of July, with occasional bouts of severe weather as strong jet stream disturbances continuously reinforce cool air over New England.
Have a great Monday - stay cool!
Matt
