To get a high-impact snow storm in Washington in the month of March you need:
- Heavy snowfall rates to overcome the high March sun angle.
- Perfect Track: Favored meteorological “benchmark track” for big snow storms in DC is from Cape Hatteras to Cape Cod.
American Ensemble Model: The last three runs have shifted the storm track much closer to Cape Hatteras North, Carolina on Monday afternoon, also all models have slowed the progression of this system down (remember just a few days ago this was forecast to be a Sunday afternoon through Monday morning event). Good news is if we can slow down the energy a bit more (Monday night into Tuesday) then the chances of a significant snow storm for the eastern half of our region would increase.
The last three operational runs of the American GFS (Global Forecast System) model have also trended the storm track much closer to the coast on Monday:
If the trends in the GFS were to pan out, the interstate 95 corridor, points east would be under the gun for some snowfall accumulations with higher snowfall rates.
The next two images show the difference in snowfall accumulation output of the two images above (pretty significant if these trends continue today):
Last night’s 06z run of the GFS
This morning’s 12z run
The major shift closer to the coast shown in the North American Model (NAM) below made me laugh out loud (these forecast models are pathetic). Within twelve hours (poor lead time) you go from zero snow from Raleigh NC to DC and Baltimore to what would be hefty snowfall rates.
Japanese Meteorological Agency (JMA) model also shifts much closer to the coast, and in fact toward that “benchmark” of Cape Hatteras
GEM (Canadian model) also shifts storm track much closer to the Mid-Atlantic coastline
US Navy Global Environmental Model (NAVGEM) also shifts storm track much closer to the Mid-Atlantic coastline
Finally, the stubborn European Model also is slowly but surely shifting the track every so slightly northward:
Last Night’s 00z Run
Hot off the presses 12z Run
If anyone in the media writes this storm off, don’t listen, we are right on the edge of what could turn out to be a high-impact snow storm for the big cities of the 95 corridor. All we need is for the trends to continue and wham, we would have rapidly deteriorating conditions on Monday afternoon into the overnight hours with a plowable snow.
I will take a final look at the 18z suite of models coming out… and if the shift continues all I will want to see is the European model tonight. Tomorrow will either be a very exciting Sunday around here or a very disappointing one for us snow lovers. I am just being honest, that we will not know how close in to the 95 corridor impacts will be from snow until tomorrow. Fingers crossed for Winter Storm Watches… won’t hold my breath though, we have been robbed way too many times this year. Bottom Line: We can’t give up on this storm system until tomorrow morning.