*ALERT* AREAS OF SCATTERED DAMAGING WIND GUSTS FROM SEVERE THUNDERSTORMS EXPECTED, POSSIBLY UP TO 70MPH… SHOWERS/STORMS POSSIBLE BETWEEN 2-10PM, STRONGEST IMPACT BETWEEN 4-9PM FROM WEST TO EAST… HEAT ADVISORIES CONTINUE FOR MUCH OF THE REGION EXCEPT THE WESTERN HILLTOWNS, N.BERKS AND SOUTHERN GREENS OF VT… VERY HOT AND HUMID FOR THE FINAL DAY OF OUR HEAT WAVE, WHICH WILL BREAK WITH A BANG… MORE SHOWERS AND T-STORMS TOMORROW, MORE RAIN THURSDAY NIGHT INTO FRIDAY WITH MUCH COOLER CONDITIONS DEVELOPING… HOLIDAY WEEKEND LOOKS UNSETTLED… SEASONABLE WARM-UP EARLY NEXT WEEK… KEEP AN EYE TO THE WESTERN SKY TODAY, FOLKS, AND *GET INSIDE* WHEN STORMS APPROACH… 7:10AM WED…

Good morning everybody, we’ve been going through a tough stretch of weather, and today will be no different. I will detail the big picture immediately below, and go into the report below that, so please scroll to get what you need/want.

BIG PICTURE
We have a large upper level trough (i.e. area of lower pressures aloft usually associated with cooler air) over the Great Lakes and south-central Canada, circulating counterclockwise.

At the same time we have a strong upper level ridge (i.e. area of higher pressures aloft usually associated with warmer/hotter air) in the northwest Atlantic, circulating clockwise.

The clash between these two disparate air masses is creating a huge convergence zone (where these two masses meet up) and producing a large area of clouds, showers, downpours and thunderstorms over the upper Midwest, western NY/PA, and the eastern Great Lakes region.

The upper low is winning the tug-of-war battle today (yes that reference confirms that I’m ancient), and will be pressing that entire disturbed pre-frontal area southeast and into New England this afternoon.

Meanwhile, we’re clearing out in southern New England after some leftover clouds from overnight showers and storms lifts northeast and out of here.

This will allow sunshine to develop quickly this morning from south to north (already has in many places), and in turn will foster temps rising well into the 90s for one more day (upper 80s in the higher terrain and north of the MA border outside of the valleys).

Copious amounts of instability will build across the region today, and with incoming strong-enough unidirectional wind shear (i.e. wind speed changes with height, but not its direction), we will see numerous showers, downpours and thunderstorms develop by early to mid afternoon over central and eastern NY state, pressing east.

Some of these thunderstorms will turn strong to severe, and are expected to produce isolated to scattered damaging wind gusts of between 50-70mph, which can cause tree damage, line damage, property damage, and power outages.

Two people were injured in the severe thunderstorm in Hartford County last night, in Enfield, just south of Springfield when a tree fell on their house and trapped them.

This is very unfortunate, and I’m hoping that this post will be distributed to others you know in the region, with the hope that folks will at least get inside when storms approach today, and away from windows, and preferably in a part of your home where any falling trees are most likely either not to be able to reach, or if they do, would cause less damage in those spots, then in areas of your home closer to a falling tree.

DAMAGE REPORTS
https://forecast.weather.gov/product.php?site=NWS&issuedby=BOX&product=LSR&format=CI&version=1&glossary=1&highlight=off

HEAT SAFETY TIPS
https://www.weather.gov/safety/heat

SUMMAHRY OF IMPACTS
–Temps this morning in the 70s will rise into the upper 80s to upper 90s for another day
–Heat indices will climb into the mid 90s to mid 100s (not 150º, but more like 105º)
–Dewpoint temps will remain/rise into the upper 60s to mid 70s
–Take precautions as per the last 2 days to manage stress caused from high heat and humidity, and stay hydrated
–We’ll be mostly sunny through the noon hour or, and possibly very early afternoon, but showers and thunderstorms will be approaching eastern NY from the west
–Surface CAPE values (Convective Available Potential Energy) will rise to between 2000-4000 Joules Per Kilogram, which may be gobbledybook to you, but to me indicates a high level of instability that will have developed to fuel incoming storms
–Between 2pm-4pm some isolated showers, downpours and thunderstorms will arrive into the Taconics, Berkshires, Litchfields or southwest VT and press east
–Between 4-9pm, clusters or lines of strong to severe thunderstorms will be developing and will likely cause some pockets of wind damage in the region, with straight line winds being the main threat
–There is a low chance for a weak tornado to form in northern portions of southern VT and southwest NH, but is unlikely
–Frequent lightning will be seen in some storms today, and torrential rain will be developed by strong updrafts in these storms. Hail is a secondary threat.
–This storm activity will be what breaks the heat wave
–However, humidity will remain through Thursday night as a cold front still has to work through the region Thursday night into Friday
–Lows tonight will only drop into the upper 60s to low 70s with a possible shower or t-storm overnight, continued muggy
–For Thursday, the convergence zone prior to the front passing through will be riding herd over southern New England, and produce a mostly cloudy day with perhaps a few sunny breaks at times
–Highs will be much lower, in the upper 70s to low 80s but dewpoints will continue near 70º
–Scattered showers and thunderstorms will be possible, and we can’t rule out an isolated strong to severe thunderstorm which takes advantage incoming increasing wind shear, and leftover moisture at the surface
–By Thursday night into Friday morning, I think we could develop a more stratiform type widespread rain shield as the front pushes in and through the region with a strong southwesterly mositure feed working WSW to ENE into the WMass region
–Lows will be cooler, down into the low 60s
–Friday looks cloudy, showery, unsettled, and much cooler with highs only in the upper 60s to low 70s, with lows in the upper 50s with more scattered showers possible
–Over the weekend, after today and tomorrow’s pre-frontal storminess, and after Friday’s cold frontal passage, we THEN have to deal with the upper low responsible for all this weather and its passage through our region
–This will foster MORE unsettled conditions
–This means scattered showers will be possible both weekend days, including the 4th, with highs only in the upper 60s to low 70s Saturday, and well into the 70s on Sunday, when we could also have some natural fireworks in thunderstorm form
–Early next week looks warmer, with highs climbing back into the 80s to near 90º (but not in the 90s) through Tuesday before another frontal boundary tries to cool us back down by mid week

I know this was a lot, but between our heat wave, severe weather today, much cooler and rainier weather late week into the weekend, and the 4th of July holiday, I had to cover a lot.

Have a great day, and PLEASE check back with me throughout today. I will report again by noon or so, and then be in the weather saddle all afternoon and night until this threat passes us and is over.

Please help distribute this information to others in the region, and I will be looking for your reports today!

Thanks very much, Dave