IIRC don Sutherland posted in here in that past that 4 out of the 5 tops five La Nina snowfalls at BWI were in January, and were all under 10" of snow. The lone exception was the Blizzard of 1996.
I know it's the NAM, but it's scored last minute events like this in previous times. There were several events in the 2013 - 2015 time frame where it picked up on some mid level warmth of subsidence that even the Euro didn't detect. To see the NAM and some other meso guidance trend lower/more disjointed is a bit of a red flag.
Never dance on the grave of a snow lover. It invites back luck for you.
Really impressive temp drop over the next 24 hours. It's amazing to realize that today might be the warmest day for the rest of the month.
That was an epic storm. 24" of snow in Damascus, 5" in Takoma Park. We had nearly dry roads in southern Montgomery County, while upcounty it was snowing hard.