Potential Snowfall Accumulations through 3AM Thursday.
- Winter Storm Watches are issued 36 hours prior to a Winter Storm and for the Washington DC Area, they are issued when snowfall amounts of 5″ or more are likely.
- I expect that the National Weather Service will issue Winter Storm Watches Monday.
- The trickiest part of the forecast is for locations just east of the 95 corridor. It is across these locations that cold air will be slower to move in from the west as the storm is deepening off of the Del-Mar-Va coastline. Snowfall totals in the eastern most suburbs including the eastern shore of Maryland may need to be raised in future updates.
- If it were mid or even late February a 15 to 30″ snowfall would be likely from the Shenandoah Valley across the Interstate 66 corridor eastward (including Downtown Washington) to southern New Jersey.
- Temperatures will be marginal (lower 30s) so this will be one of those slushy, heavy, wet snows that can do a lot of damage to trees and power lines. With precipitation starting out as rain and then switching over to heavy, wet snow, I think 8 to 12″ totals are going to be common outside of the urban heat island with some locations in the foothills and the Piedmont (beautiful horse farm country of Northern Virginia) picking up in excess of one foot of snow!
- The European Forecast Model has been very consistent in keeping the heaviest snow from getting much further north than the Maryland-Pennsylvania border, I will be watching the GFS to see if there is any shift south in track tomorrow…but as it is now the immediate D.C. Metropolitan Area looks like it will be getting a significant, High-Impact Winter Storm Tuesday night through Wednesday night. Stay Tuned.