Hang On To Your Hat Monday; Strong Winds Coming

I had made much of the remarkably calm November we had here in Vermont. Normally a windy, stormy month, we had a lot of tranquil days with welcome light winds.  

Fallen trees in Milton, Vermont after a severe wind storm
in October, 2017.  We might have some trouble with
broken trees and power lines with a storm coming
along for Monday. 

Those days are gone. December is turning out to be pretty damn gusty.  The cold front that blew through early Friday prompted its share of gusty winds. Those were enough to cut power to 2,200 homes and businesses in Vermont for awhile. 

Even more of that is coming.

First, we have a wimpy little system coming through today.  We won't have a lot of wind, or even a lot of snow out of this. But it could produce some briefly moderately heavy snow showers in some areas this afternoon and evening.

That means there will be spotty trouble with slick roads and briefly poor visibility, so watch out for that.   Even so, the vast majority of us will see an inch or less of accumulation.

It turns out the storm coming along Monday is meaner than I was thinking a few days ago. 

As the National Weather Service in South Burlington points out, this storm will be strengthening as it passes by a little to our north and west on Monday. It will also be accompanied by something known as a low level jet which is accompanying the storm. 

A low level jet is essentially a packet of fast moving air a few thousand feet above the surface. In this case, winds a little above the summits of the Green and White Mountains and above the Adirondacks could be screaming at 85 mph on Monday.

Thankfully, we won't have winds at that strength down here where all of  us live.  The question is: How much of those winds can mix down to the ground in the turbulent atmosphere of the storm?

As temperatures rapidly rise in the warm side of the storm Monday, there's a bit of an inversion forecast at a level of the atmosphere a little below this low level jet.  That inversion - a layer of the atmosphere in which the temperature increases with  height - acts as a lid, preventing much of that high level wind from curling down toward the ground.

It will still be very windy, but not as windy as it could be.  There are of course some questions as to how strong that inversion will be.  That means there is some question as to how strong the winds will get.  The National Weather Service is saying they won't be surprised to see some gusts in the 40 to 50 mph range.

Then the storm's sharp cold front comes in Monday afternoon and evening.  That will create a line of showers, some of them heavy.  There could even be an isolated rumble of thunder or two.  This line of storms could push some of that high level wind down to the surface, causing the kind of gusts you might get with a strong or severe thunderstorm.

The cold front will wipe away that inversion I talked about, so gusty, possibly damaging winds could continue Monday night, especially on the eastern slopes of the Green Mountains and Adirondacks.

Bottom line: We could well be dealing with some fallen trees and power lines Monday and Monday night. Stay tuned for that. 

Next up in the active weather pattern is the next, colder but somewhat weaker storm on Wednesday. There's a lot of questions as to how much snow this might produce.  It could be not much, or it could be moderate accumulations. We don't know yet. Wednesday's storm will be less windy than Monday's at least here in Vermont. 

After that, another potentially windy storm could swing by around next Sunday.