A Very White Thanksgiving: First Snowstorm of Winter Coming

At least 8" expected by midday Wednesday

Paul Douglas
November 25, 2019 - 11:26 am
Plowable snow

MnDot file photo

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Mother Nature has a wicked sense of humor. Exhibit A: the forecast for Thanksgiving travel has been complicated by a southern storm, brimming with moisture from the Gulf of Mexico. A deep layer of cold air aloft should mean all-snow, starting late in the day Tuesday, peaking Tuesday night, before gradually tapering off Wednesday morning. If you leave now, you may just get to work on time Wednesday morning.

Overdue for a Big November Snow. The first big storm of the season is always problematic. Even long-time winter weather veterans need a little extra time to acclimate to slippery, snow-covered highways. But snow in late November is hardly unusual. In fact, according to the local National Weather Service office in Chanhassen we are long overdue for normal amounts of November snow in the Twin Cities. Average 30-year November snowfall in the metro area is 9.3", and we may pick up the majority of that with this next storm.

Expected snow
Praedictix

Very Plowable. Latest models print out over .9" liquid, which (with a standard ratio of 10:1, snowfall to liquid) would translate into roughly 9" of snow, so the map above seems reasonable (wrong word) in terms of snowfall totals. Something in the 5-10" range, factoring in relatively warm ground temperatures and compaction of snow (this will be a heavy, wet snowfall) seems like the correct range, up from the 4-7" we were predicting earlier.

European model
WeatherBell

European Model Prediction. Meteorologists are secretly relieved when weather models agree, which doesn't happen very often. In this case both NOAA models and ECMWF (European) model are pretty much aligned, printing out some 7-10" amounts across the metro and the southeastern third of Minnesota and western and northern Wisconsin by midday Wednesday. A significant pile of slushy snow.

Storm watches
NOAA and Praedictix

Winter Storm Watch Issued. NOAA has issued a Winter Storm Watch, valid from Tuesday evening through Wednesday morning for the Twin Cities metro, with a "significant impact on holiday travel". No kidding. If you can delay your trip over the river and through the woods to grandma's house until the PM hours Wednesday, I suspect the freeways and interstates will be in better condition. But Wednesday morning travel may be a gong show.

NOAA update
Twin Cities National Weather Service

Twin Cities National Weather Service Update. On our scale from nuisance to plowable to crippling this should wind up being a plowable snow event. Traffic will probably be (very) slow Wednesday morning, but people will still get around. I don't think this will rise to the level of a crippling snowfall.

As far as the atmosphere is concerned winter is here. The sun is as high in the sky as it was in mid-January, so none of us should be shocked about snow in the forecast. Check your tires, makes sure you have a brush and scraper in your vehicle, and if someone else plows your driveway you might want to get those driveway stakes in the ground (now). Statistically, we're due for a real snowstorm - and it looks, increasingly, like a headline-leading snowstorm is on the way. Let it snow, let it snow, let it snow!

Make it snow
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