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| Snow and sleet forecast accumulation map from the National Weather Service in South Burlington, updated late Friday afternoon. Still a low-confidence forecast, as there's still lots of questions about to what extent sleet and freezing rain will enter the picture. |
We still get a decent thump of snow, but you're also going to be dealing with potentially a thick layer of sleet, and possibly harder freezing rain ice with this ugly system.
The predicted overall chain of events hasn't changed much since this morning, except for the fact that even more sleet and freezing rain is win the cards than predictions indicated this morning. At least in the opinion of many, but not all local meteorologists.
As we've been saying all along, the worst of the ice should hit southern Vermont, but all of us should get at least some sleet. Unfortunately, most of the heaviest precipitation rates will coincide with the time that sleet and freezing rain are likeliest.
To nobody's surprise, the winter storm watch we had this morning has been upgraded to a winter storm warning statewide. A watch means conditions are favorable for a storm, a warning means it's happening now or inevitable.
We're still in the inevitable category because there's no really dangerous weather coming in until Saturday night, really. The warning goes from Saturday evening until early Monday morning, so this is no quick hitter like the last few storms have been.
This will be the worst winter storm Vermont has seen this year. It might not be the worst winter storm we've ever seen, but it's one to take seriously.
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| Still a lot of questions as to how much freezing rain will enter the picture with Sunday's storm. |
Let's break down the chain of events
TONIGHT:
Partly cloud and cold. Lows will be within a few degrees either side of zero. Other than needing to dress for the conditions, there's really no weather or travel concerns today.
SATURDAY
It's your day to stock up on supplies if you need to. If there's any morning sun, it will fade behind increasing, darkening clouds through the days. Light snow will begin to spread southwest to northeast across the state in the late afternoon. It'll stay cold, with highs staying near 20. Snow might not reach the Northeast Kingdom until well after dark.
SATURDAY NIGHT
Snow will continue. Lightly at first, but picking up steam as we approach dawn. It'll still be too cold for any sleet, except maybe late at night in far southwest Vermont. Most of us should have a decent two to four inches of new snow by the time dawn breaks Sunday.
SUNDAY
Here's where things get more dangerous, and more complicated. And thus, harder to forecast. What I'll outline is what the National Weather Service thinks will happen as of Friday night. But it could change. If it does change, I think the trend might continue away from snow and more toward sleet and freezing rain.
If our scenario plays out as planned, it'll be snowing pretty hard Sunday morning. But things will starting mixing with and changing to sleet and, eventually freezing rain in many spots starting in the late morning.
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| If there's more freezing rain than expected with the upcoming storm, tree damage and power outages could come into play. We're unsure of this so far. |
The snow will start out light and fluffy early, but become wetter and heavier as the morning goes on.
Not because it'll be all that warm down here on the ground. But because the snow will start to partly melt as it falls through a warm layer high above
This has implications for power outages. The wetter snow will start to sag and weigh down some trees. It won't be enough to cause the power lines to break, but it'll help set the stage for problems later.
The sleet will add to the weight, but at least some of it tends to bounce off and not stick to things.
But now, it looks like some freezing rain could make it all the way to the Canadian border. The mix or sleet or freezing rain could last six to eight hours, if the National Weather Service is correct.
That said, opinions as of Friday evening among local meteorologists are pretty divided. The National Weather Service has sleet and possible freezing rain all the way to the Canadian border by perhaps noon. Other meteorologists question whether the changeover will happen that fast, or last particularly long, or even if there will be much sleet at all in far northern Vermont.
I don't know which is right, and no meteorologist in their right mind has a lot of confidence in the forecast right now.
But I do know that you should plan on not driving anywhere on Sunday, and plan on perhaps anything frozen or freezing coming from the sky, be it snow, sleet or freezing rain. A complete changeover to plain rain is not in the cards, except just maybe in extreme southern Vermont, like in Bennington or Brattleboro.
Even there, if it goes to plain rain - a big if - that won't last long. It's definitely going to be a snow and ice event for us.
If there's a fair amount of freezing rain anywhere, that will add to the weight of the snow on trees and power lines. Then, the wind will pick up Sunday evening and overnight, and that's where we'll see the risk of some power outages.
This won't be anything remotely like the Great Ice Storm of 1998, but we do face the risk of scattered power outages. The biggest risk of a fairly thick layer of ice from freezing rain with this storm is in southern Vermont.
SUNDAY NIGHT
The mix goes over to snow, and tends to become lighter in most places. Northern Vermont is most likely to continue to see some snow accumulations overnight. It'll get windy, with gusts to over 35 mph in many spots.
MONDAY:
The snow showers will continue in the mountains. Up there, a few to several inches of snow will fall. In the valleys, there will be little accumulation. But it will be a miserable day, with cold winds continuing to gust past 35 mph in many areas. Temperatures will stay in the teens, and wind chills will e below zero. Blowing snow will add to the Arctic wasteland feel to the day.
BOTTOM LINE
The National Weather Service is still expecting total accumulations of snow and sleet to be in the six to nine inch range statewide. There's still a big bust potential. If the warm air aloft really wins out, there would be less, maybe three to eight inches, with a lot of ice, which would suck.
If the warm air aloft turns wimpy, we could see more than a foot in parts of northern Vermont and easily six to 10 inches south before.
I'll post another update Saturday morning, as I'm sure we'll have further updates and forecast refinements.
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