Confidence Growing On Damaging Vermont Windstorm Tuesday Night/Wednesday As Storm Hammers U.S

When the National Weather Service web site home
page gets this colorful, you know there are a lot
of weather threats in the nation. This map 
is from this morning. 

 The developing storm that promises to hammer most of the United States has spread a remarkable number of weather warnings across the nation.  

A blizzard will envelop most of the central Plains, with heavy snow and wind extending up to the Great Lakes in the next couple of days. 

A tornado outbreak now seems like a good possibility from Louisiana to North Carolina. The threat of severe flooding extends from Georgia to southern New England. Wind advisories and high wind watches and warnings extend from New Mexico to Maine. 

This is going to be one humdinger of a storm. That includes us in Vermont

VERMONT EFFECTS

The biggest threat from this storm in the Green Mountain State is high winds, though wet snow, rain and flooding are some secondary concerns.

High wind details

In their forecast discussion early this morning, National Weather Service meteorologists said they have gotten even more confident that Vermont was in for a nasty blow.  This could easily be comparable to October, 2017 or December, 2022. Both those storms caused a ton of damage. 

Although there could always be something that short-circuits the winds so they're not so bad, so far we're not seeing that kind of break. 

If the forecast holds, expect tens of thousands of power outage and lots of trees down. Where the strongest winds blow, mostly along the western slopes of the Green Mountains, the winds would be strong enough to cause some damage to roof shingles and siding, and also threaten sheds, greenhouses and other un-reinforced structures.

I also hate to ruin anybody's lingering  holiday mood, but you probably ought to spend today taking down your Christmas decorations. They could end up blowing around and causing additional damage.

The high winds are forecast to start Tuesday evening and last into Wednesday, peaking in the early morning hours Wednesday.  

National Weather Service South Burlington issued this
wind gust prediction map. Those dark reds indicate gusts
over 65 mph forecast early Wednesday.

All except southeastern Vermont is under a high wind watch. In the watch area, gusts look like they'll at least be in the 55-60 mph range, with possible local gusts of 75 mph or even higher along the western slopes the Greens.

Wet Snow

The storm is a warm one, but it looks like it might start with a thump of heavy, wet snow, especially in the southern Green Mountains which could see six inches of "wet cement" snow late Tuesday afternoon and evening before a changeover to rain later on.

This wet, heavy snow will come as winds are ramping up. The combination of snow loading and the winds would probably make any power outage situation worse.  The northern Green Mountains will probably see less snow. Most valleys likely won't see much at all. 

But the added snow from Tuesday night, combined with the snow we had Sunday, along with the rain from this new storm, leads to......

Flooding concerns

There is a risk of flooding across Vermont, but mercifully - fingers crossed - it'll be on the minor side.

The biggest risk of serious flooding is in a zone from Connecticut, through the New York City metro area, through eastern Pennsylvania and to Maryland. Especially  heavy rain will hit there, and snow from the weekend storm will melt rapidly, leading to worries about a serious situation there.

Here in Vermont, the rain won't come down quite as hard, and the initial thump of precipitation will be a mix. That said, rainfall totals of 0.75 to 1.5 inches, along with melting snow Wednesday do pose something of a threat.

At this point, I expect some ponding of water in low spots, especially since the ground is partly frozen and water won't soak in so easily.  Rivers will see sharp rises, but so far at least, they either won't reach flood stage or just overflow into floodplains. 

This bears watching, though. If the rain is heavier than expected and/or if temperatures soar above the predicted 40s, we could be looking at a somewhat worse flood situation.

BOTTOM LINE

Meteorologists are remarkably confident about this storm having some real impacts.  Details in the forecast will of course be refined and shifted before the event arrives. 

We've been having too many big storms over the past year. This year does not seem to want to get any quieter.