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| That familiar Vermont sky before a snowstorm: High clouds moving in over St. Albans at 9:45 a.m. today as our big snowstorm approached. |
And sure enough, it's on its way. Pretty fast, I might add. I noticed how much darker the sky was just a half hour after I shot the photo you see in this post.
One way to tell this will be a high impact storm in the Northeast is that I got a robocall from my homeowners insurance company this morning warning me to take precautions. These robocalls usually come when a wide area is going to get hazardous weather.
Sure enough, this storm is beginning to cover a wide area that includes the eastern Great Lakes and most of the Northeast.
Here in Vermont, I saw no major changes to forecasts between Friday and this morning, so expect a really good thumping of snow later today through Sunday. Most of Vermont outside the far northern Champlain Valley is still expected to get at least a foot of snow out of this, and some spots in southern Vermont will close in on two feet by later Sunday afternoon.
This is certainly a larger than average storm that everyone should take seriously. It won't be the Worst Storm Ever, but it won't exactly be a flurry either.
WRINKLES IN THE FORECAST
This is precisely the type of storm that often surprises. As noted yesterday, there's an incredibly sharp temperatures contrast setting up with Arctic air north and west of the storm track and very mild air just offshore to the east.
This tight temperature contrast was already setting up this morning. Here's an example: At 9 a.m., it was 5 below zero in Highgate, Vermont, in the state's far northwest. At the same time, it was 1 above in Burlington, 9 above in Rultand, and 22 in Bennington.
My experience is the tighter the temperature gradient in a storm, the more likely it is that there will be surprises. In every winter storm, a few areas will get less snow that forecast, while others get more than expected. That's just the nature of the beast.
I think there might even more unexpected developments with this storm than with most winter weather event. I don't know what those surprises might be because they are, um, surprises.
Already, I've seen one minor curveball with this storm and it wasn't even here yet as of this writing. (10:30 a.m.)
The temperature contrast is so strong that it set up a little weather front of sorts in southern Vermont and New Hampshire, Light snow and flurries were already falling along that semi-front ahead of the storm.
A few things to watch for:
1. The dry Arctic air feeding into the storm might (or might not) cut back on the amount of snow that fall in far northern New York and perhaps the northwestern tip of Vermont. Dewpoints were in the teens below zero this morning in this region, an indication that the air is very dry.
At the very least, it will take awhile for the oncoming snow to saturate the air up in these regions later today and tonight. Which means at first, the snow could evaporate before it hits the ground. All this could reduce the amount of snow that falls there.
The flip side: If the storm's moisture pushes northward more than expected, the areas I just describe could end up with more snow. Far northwest Vermont and northern New York to me are the hardest parts of the area to predict with this storm.
2. It's possible a band of particularly heavy snow could set up somewhere in southern or central Vermont. If it does, it's impossible to know in advance exactly where that would happen. If this occurs, we might end up with a narrow zone of snow accumulations exceeding two feet, maybe reaching two and a half feet.
3. At least one computer model has the warm air aloft getting further north than expected tonight. That might force the snow to mix with or change to sleet for a time in far southern Vermont late tonight or Sunday morning.
4. The National Weather Service in South Burlington is noticing the extreme temperature contrast between the still-open part of Lake Champlain and the bitter cold coming in Sunday night and Monday. That could keep lake effect snow going along some of the western slopes and parts of the central and southern Champlain Valley. That might be good for another two to four inches of snow later Sunday night and Monday there, while everybody else would get nothing more than flurries.
TIMING:
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| This is the Saturday morning predicted snow accumulation map from the National Weather Service in South Burlington. As you can see, it doesn't look much different from yesterday's map. There have been no major changes to the overall storm forecast, but there are a lot of wrinkles within it. |
It won't come down particularly hard at first, but the roads will get snow covered and slick. It's too cold for salt to work well, especially north. Don't expect it to warm up, especially central and north, as temperatures stay in the single digits.
Saturday night: Lots and lots of snow overnight, especially after 10 p.m. In southern and central Vermont, snowfall rates could go up to one to two inches per hour. Visibilities will be very poor, snow plows won't really be out in force and will have trouble keeping up with the storm.
Don't drive anywhere. It will be cold, too with temperatures near 0 north to low teens far south.
Sunday morning: Heavy snow during the peak of the storm. A mix or brief change to sleet might happen in far southern Vermont. Winds will be picking up, too, so blowing and drifting snow will again be a problem. Stay home, don't drive anywhere. It will be a great time to watch the drama of the storm through your windows, from inside your house. Still very cold, especially north.
Sunday afternoon: The snow won't come down quite as hard, but the winds will continue to pick up, gusting to 35 mph in many areas. The blowing and drifting will be abysmal. Visibility on roads will be a problem. Road crews will have trouble keeping up with the drifts. Wind chills by this time will be dangerous, falling well below zero. I'd continue to stay home.
Sunday night: Absolutely brutal. There will be lots of blowing and drifting snow as winds continue to gust as high as 35 mph. Actual temperatures will go down to between 5 and 15 below, with wind chills ranging from 20 to 40 below. It's not a good idea to go outside. Flurries will continue, with a good chance of some lake effect snow off Lake Champlain.
Monday: Still awful. Temperatures will stay at or below zero for many of us all day. Gusty northwest winds will continue the dreadful wind chills. It does get somewhat better later in the day as winds subside somewhat. After a frigid Monday night, temperatures will start to moderate a bit on Tuesday.
THE STORM ELSEWHERE
Vermonters should count themselves lucky that most of us will just get snow, wind and blowing snow.
Forecasters are pulling their hair out in southern New England, southern New York, New Jersey and Pennsylvania. Depending on where you are down there, people face areas of heavy, deep snow, or freezing rain that could ice up trees and power lines enough to have them come crashing down.
Other areas closer to the coast will get a thump of snow, then heavy rain that could cause flooding. Speaking of flooding, the storm might cause coastal high water and battering waves at the time of high tide Sunday morning.
Places that do get above freezing down there will experience a flash freeze later Sunday, when all that water ices over instantly. Yuck.
In the South, this storm was bringing the threat of severe storms and tornadoes to the Gulf Coast states. I noticed some tornado warnings in Mississippi this morning. I've already seen reports of damage from possible tornadoes in that state this morning.
AFTER THIS STORM
The weather pattern looks active and complex Wednesday into next weekend. I'm not even going to hazard a guess as to what kinds of things await us then, but expect some sort of storminess and snow and whatnot. There's a real chance that what will be a deep snow cover in Vermont could get even deeper. Stay tuned.
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| National Weather Service meteorologists are doing an excellent job forecasting this storm, despite the fact they are not being paid due to the government shutdown |
National Weather Service meteorologists are working without pay during this government shutdown. When you get a storm as dangerous, widespread and complex as this, these meteorologists have to work extra hard, and really pay attention to the tiniest details to get the forecasts right.
They are doing a tremendous job, despite the obvious hits to morale. These meteorologists are cranking out timely warnings right on cue. I'm sure they're saving lives.
Beyond this storm the weather across much of the United States looks like it will remain, complex, active and potentially dangerous in spots. And they will keep working.
Please hug your local National Weather Service meteorologist.
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