Update on arrival of snow in time for December 1st

Countdown to the Big Game on WOWK
February 07 2021 06:00 pm

(WOWK) – A quiet weekend of weather will literally be the “calm before the storm” with an expected large area of low pressure bringing the region rain and snow between Monday and Tuesday and a much sharper cold snap as well.

Weather model output for Monday morning November 30, 2020

The strong area of low pressure should come in with rain late Sunday night and sit right over the WOWK viewing area early Monday. There will likely be a dry gap in the weather for a few hours and the low swings by only to be followed by the rush of cold air and the change from rain to snow starting in the western counties late Monday afternoon and evening.

Weather model output for Tuesday morning December 1, 2020

By Tuesday the winds will blow from the northwest and the snow showers will fall across much of the region but the low will continue lifting to the northeast, taking the snow with it. Wind speeds could easily gust to 20 mph or more meaning the “feels-like” temperature will be a lot colder than the projected actual temperatures.

Model output of temperatures Tuesday morning

The temperatures will be cold enough for the snow to stick on the grass in particular on Tuesday morning but also on some of the area roads.

There are multiple weather models that show a variety of different scenarios and they have been changing their calls on how much snow we see with regularity. As of Friday some of the models, including our Predictor, are showing some consistency. It should be noted that the model output below does NOT take snow melt into account. This is showing the amount of snow before melting. Melting tends to result in lower actual amounts.

Snow output from Predictor for Monday night-Tuesday. (Created Friday afternoon 11/27)

There are multiple methods of looking and utilizing weather models, including taking the base information, creating many computer generated small differences then basically averaging them out. This tends to eliminate wild high or low end scenarios and also helps smooth incorrect biases within the models themselves. Below is our representation of what is known as the “ensemble output” which in this case also tends to agree well with the single-model output from Predictor above.

Representation of model ensemble outputs. (Created Friday afternoon 11/27)

So impacts we expect include:

  • Heavy rain very early Monday morning
  • A gap in the rain Monday afternoon
  • Snow mixing in with the rain and changing to all rain in the western counties late Monday PM
  • Snow working to the east, touching almost all of the area before sunrise Tuesday
  • Slick roads even with only light accumulations Tuesday morning
  • Cold winds late Monday night into Tuesday morning
  • Snow to lift northeast on Tuesday, with only a few squalls left through the afternoon.
Wet Monday to a snowy start Tuesday

The sharp drop in temperature takes us through an extended period of below-normal numbers for several days. It’s time to find the big coats, the hats and the gloves or mittens, especially for the nights which will be in the 20s at times.

Temperature trends for November 30 – December 3, 2020

We FULLY expect changes in this forecast as the data becomes better and the models get a chance to work with that more accurate data. Stay tuned to this website for changes and be sure to get the StormTracker 13 weather app to see changes as they are made and in case there are any winter advisories that area issued.

Follow Spencer Adkins on Facebook and Twitter for the latest weather developments.

For local forecasts, weather alerts, live VIPIR Radar and more, download the FREE StormTracker 13 Weather App from the Apple App Store or the Google Play Store.

Copyright 2021 Nexstar Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

Download the FREE WOWK 13 News App

Washington DC Bureau

More Washington DC Bureau

Don't Miss

Trending Stories