Good evening everybody, our cold front is pressing east into the Catskills Mountains of southeast NY and eastern PA during the 7pm hour, and will continue eastward, raking southern New England at large and the WMass region specifically between 8pm-11pm or so.
A ripping southerly low level jet streak is now moving overhead and is blowing over 80mph at times… a mile up. I just looked at velocity products, which are measuring 95mph winds a mile up just ahead of the line moving into northeast PA currently.
PROS IF WE WANT LESS WIND (WHICH WE DO)
Luckily for us, low and mid level lapse rates are poor over our region, meaning there is very little buoyancy, or support for rapidly rising air. This lack of instability also acts as prevention, helping to keep higher winds aloft from mixing down to the surface.
Therefore, aside from a lightning flash or two, very little thunder is expected as the front moves through, and no hail is expected, just brief heavy downpours, with showers that are already moving through the region associated with a warm front that is nosing north into the area, ahead of the cold front hot on its heels!
CONS TO GETTING LESS WIND
However: not so lucky for us, is that there is very strong wind shear that will move through the region with this squall line, and when combined with that line of heavy showers and downpours, stronger wind from aloft could be mixed down to the surface and overcome this lack of instability in place.
In addition, temps and dewpoints are set to surge BRIEFLY into the 50s in north-central/northeast CT up into Hampden County and southern Worcester County, helping this stronger wind mix down.
So, the wind shear piece and the brief warming at the surface piece could still combine to bring 40-60mph wind gusts to areas along and south of the Pike in MA and CT.
Regardless, I think the higher your elevation throughout the WMass region, the closer you are to that low level jet streak, meaning I am expecting it to howl 40-60mph in gusts up there at times, as it’s already blown to 52mph at Bennington, VT airport.
The rest of us should see more like 30-50mph in gusts in the central/northern CT River Valley, northern Worcester County, etc.
Unfortunately I can’t pinpoint who is going to get what, but the bottom line is that AT LEAST isolated power outages are expected tonight with this squall line passage, and it’s possible that we could see more numerous outages if the instability is overcome by the factors outlined above.
Bottom BOTTOM line… make sure your devices are charged and be ready for an outage, should one visit you.
I’ll also be watching for the wind shift behind the front, which should produce westerly wind gusts between 25-40mph at times later tonight and into the pre-dawn hours.
I will post again in about an hour when this line is on our doorstep.
Thank you, and please let others know to be inside and away from windows when this line moves through, thanks… Dave
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