Increasing Potential for a Major Winter Storm on Sunday/Monday
For the last few days, weather models have hinted that there will be yet another major snow and ice storm early next week impacting areas from Missouri to the Mid-Atlantic.
A low pressure system is expected to develop in the south-central United States late Saturday night — the low is seen in the above GFS model forecast centered over western Arkansas — and begin to move east across the southeast during the day on Sunday.
As moisture associated with the low approaches cold air being funneled southward into the Mid-Atlantic by a high pressure over Canada, precipitation is expected to change over to snow and ice Sunday night and into Monday.
It appears that all modes of wintry precipitation — rain, snow, sleet, and freezing rain — are possible from Kentucky eastward through North Carolina and north up through Pennsylvania and New Jersey. Exact totals are hard to pinpoint right now as small changes in the actual track of the system will result in large variations in snow and ice accumulations, but the specter of a major storm is enough for the National Weather Service (NWS) to begin raising caution flags.
The Weather Prediction Center (WPC) says there's a greater-than-50% chance for at least one tenth of an inch of ice from freezing rain across many areas from Missouri eastward through Virginia.
The opportunity for a disruptive snowstorm is greatest in the Washington D.C./Blue Ridge Mountain region, where there is a greater-than-50% chance for more than 8" of snow in roughly a triangular-shaped area from Charlottesville, VA to Washington D.C. to Pittsburgh, PA.
It's worth noting that there is huge variation in the models right now on exactly how much snow/ice will fall. For example, here is a meteogram for Washington National Airport showing the model spread on predicted snowfall accumulations.
Regardless of how much snow or ice actually falls, this system has the potential to disrupt travel during the day on Sunday and Monday, especially in the Washington D.C. metro area as the worst of it is expected to hit on Monday.
Keep track of updates from your local National Weather Service as more model runs come in and forecasters get a better handle on the situation.
[Image credits: InstantWeatherMaps / TwisterData / WPC / WPC / Iowa State]