For perspective, the average December snowfall at IAD, DCA, and BWI is: 3.5", 3.0", and 2.3" respectively. A lot of folks are going to get their December average snowfall in under 6 hours and there's still two weeks left in the month.
Sterling WFO is releasing a special 18z balloon. It'll be worth checking when it's posted on SPC's page, especially for the lower Susquehanna Valley crew that's worried about mixing.
It's snowing a solid clip in Reisterstown. So long as it's not washed away this evening I'll be happy. Snow on Christmas decorations is like double secret bonus snow.
HRRR is colder and a bit SE with the surface low. It still has DCA as frozen at 2:00 pm today. That's a good benchmark to see how well it's handling things.
Hey all, just wanted to pop by and say it's now steady -SN in the NW Baltimore County. Looks like we're running a degree or two colder at least at the surface than forecast. The 06z 3k NAM doesn't appear to be handling the start time very well down there. It didn't move precip into Baltimore until about 1pm and we've already started. Just something worth noting for up your way.
Some good news, especially for the I-95 crew and the immediate low landers. Frederiskcburg and Louisa, VA were -RA at the start but once the heavier precip moved in they've not flipped to -SN. Even Quantico, which is right on the river, has -SN now so there might be a bit more 'boom' with the snow thanks to the earlier onset.