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Posted at 03:56 PM ET, 12/12/2012

White Christmas tracker, December 12


The European Model shows a significant storm next Wednesday over the Chesapeake Bay with rain except snow at high elevations in West Virginia and western Maryland. (StormVistaWxModels.com)
We’re now within two weeks of Christmas, but as to whether there will be snow on the ground in Washington, D.C., we’re no more confident.

There’s a lot of support for a storm coming up the East Coast next Tuesday into Wednesday. But most indications, at least right now, are that rain would be favored in the D.C. area. We’ll keep a close eye on this scenario in case the storm takes on a colder, snowier look.

Beyond that period, it may be on the dry side running up towards Christmas with somewhat colder than average conditions. We certainly can’t rule out another storm system in this stretch, but it’s timing, form, and strength is outside the range of predictability.

For its part, the GFS model continues to advertise no snow on the ground for the Washington, D.C. metro region on Christmas Day. And it shows even less snow to D.C.’s north and west compared to yesterday.


Predicted snow depth Christmas Day at 7 p.m. EST from GFS model (WeatherBell.com)
The CFS version 2 model, however, continues to be bullish about snow prospects in the 5-days leading up to Christmas.


Predicted maximum snow depth between late December 20 and late December 24 by four runs of the CFS version 2 model. (WeatherBell.com)

All four of its simulations show light to moderate maximum 5-day snow depths in the D.C. area with generally heavier amounts in the mountains. Of course, this model does not provide information about what portion of these maximum amounts would remain on the ground Christmas Day.

All told, I’ll stick with Dan’s assessment yesterday :the odds of having snow on the ground Christmas Day in D.C. are just slightly higher than the historical average (see above) of just over 10 percent.I’ll say 15 percent odds right now based on at least the *chance* for one or two storms that could produce snow as well as some cold weather as Christmas draws closer.

Related: How often does Washington, D.C. have a White Christmas?

Our standard disclaimer about the model predictions above applies: these forecasts more than a week into the future are very unreliable. They have not demonstrated the ability to accurately predict the weather this far out in time.

We’re showing you the models so we can see how they evolve (i.e. do they shift snowier, less snowy, or constantly flip flop?) and then, in hindsight, evaluate how well or poorly they simulated reality.

Previous White Christmas Trackers:

December 10, 2012
December 11, 2012

By  |  03:56 PM ET, 12/12/2012

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