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| Skies looked rather volatile last evening in St. Albans, Vermont as a burst of cold air from Canada stirred up some showers, clouds and downdrafts. |
While the northern hemisphere is warming up as the sun angle rises, it takes time to scour the pools of biting, winter cold air out of the Arctic.
These pools of frigid air tend to wander around up there as pieces of them get dislodged, inching the north toward spring.
That cold pool for now is near Hudson Bay, Canada, which means it's in fairly close proximity to us her in Vermont.
Lucky us! For now, the pieces of nippy air that are breaking off from that frigid swirl of air in Canada are landing on, or at last near our doorstep. I refer to those pieces breaking off as bowling balls because they're compact, roll down from the north quickly, then move back off to our north and east just as fast.
They're sort of drive-by cold snaps, if you will.
A few days ago, it looked like these quick cold blasts would largely miss us here in the Green Mountain State. That forecast has obviously changed for the worse, at least if you like spring.
We do see these pretty frequently in the spring here in Vermont. They're disheartening, but quick hitting, and spring resumes soon enough. Here's how our bowling match will play out this week.
BOWLING BALL #1
The first one, the weakest of three that we'll deal with this week, came in Saturday afternoon.
The cold front had a fair amount of oomph to it, but the air was really dry. The spring sunshine helped created updrafts that ran into the very cold air aloft. This built up towering showers clouds. But that dry air down in the lowest few thousand feet of the atmosphere evaporated some of the precipitation coming down.
The showers themselves had downdrafts to them. The evaporating rain and snow cooled the air further. The downdrafts and cold, dense air created by the evaporation rushed downward, causing those strong wind gusts at times Saturday afternoon.
I'm sure a few places gusted to over 40 mph, perhaps 50 mph. I noticed the National Weather Service in South Burlington hoisted a few special weather statements, warning of gusts that high.
It was cold enough for snow to fall in the upper elevations. Some places had graupel which is sort of a snow/small hail hybrid. Our first bowling ball also created some dramatic late afternoon and evening skies over the region. Dark clouds, shafts of bright sun, gushes of rain and snow visible here and there, and some wild rainbows.
Today is cooler, with clouds mixed with some sun and breezes behind yesterday's "bowling ball.
The second one comes through this evening and overnight.
BOWLING BALL #2
Once again the air is dry but the cold front with this is strong. That should set off some gusty winds, scattered showers, and eventually, snow showers overnight. Temperatures will take quite a tumble, and we'll see the coldest air since late March by dawn.
This by no means will be record cold, but it will be shock to the system. It'll be down in the 20s for pretty much all of us and northwest winds will make it feel colder.
If you have magnolias blooming, there's a good chance they'll become brown wreckage after this unfortunately. But the vast majority of garden plants current growing should survive just fine.
Monday will be sunny, which will deceive you into thinking it's nice out. It will be cold for the season with highs only in the 40s. The sun, gusty northwest winds and very dry air could create something of a fire danger. Tis the season for that, as I explained in a post last week.
Monday night will be cold, too, though it will warm up west as the cold bowling ball departs. Tuesday will bounce back nicely to near 60 degrees.
BOWLING BALL #3
This has the potential to be the strongest and perhaps the most disruptive of the three, depending on which computer forecasting model you want to believe.
The cold front and embedded low pressure will come in from the west and north, so rain will break out Tuesday night and Wednesday. So far so good.
Then, the cold air rushes in, changing rain to snow, yes snow, Wednesday afternoon or evening. Probably even in the valleys.
If you believe the European computer models, the storm won't linger much, so only a little snow will fall. If you believe the American model, this thing might linger for several hours, which could dump several inches of snow Wednesday evening and night. That's especially true along the western slopes of the Green Mountains.
I'm not sure which one to believe yet, but of course I'm rooting for the European model on this one.
We do know we have another hard freeze Wednesday night, and probably Thursday night, and a chilly day Thursday.
After that, it starts to warm up, and we can forget the bowling balls for awhile. We'll go back to our regularly scheduled spring.
As always, stay tuned for updates. The forecast could well change!
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