Eskimo Joe

Latest AFD from LWX: Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 907 PM EST Sat Dec 13 2025 .SYNOPSIS... An Arctic front bring a blast of snow and bitter cold temperatures to the area late tonight into Sunday. Accumulating snow will push into the mountains this afternoon before spreading east later this evening and into the overnight hours. Gusty winds behind the front will lead to plunging temperatures with wind chills values expected in the teens and single digits late Sunday afternoon. Arctic high pressure settles over the region Monday before shifting offshore Tuesday. This will yield a pattern change with warming temperatures heading into the middle and end of next week. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... No major changes to the previous forecast. Added western Loudoun to the Winter Weather Advisory earlier this evening. This is a banding type set up with favorable conditions for CSI banding. Given that, some areas will overperform and some will underperform, just the nature of banding. Snow has been the p-type observed at onset across most of MD thus far. Further south, rain may mix in at onset. Currently evaluating guidance to see if any potential extensions are necessary in the advisory further south into Prince William or Fredericksburg. Just not enough confidence at this time. Also, areas in NE MD near the PA State Line may approach warning criteria. Just something to keep an eye on.

Looking to our west, Pittsburgh upped snowfall totals along the MD/PA line. Seems like this system is rather energetic, and I would argue it bodes well for us later on tonight.

According to my records, since moving back to Maryland in August of 2016, I haven't experienced a December snowfall greater than 3.4", or an overall snowfall of greater than 4.8". Let's see what happens tonight!

RH spike to ~90% on all the Frederick, Carroll, Baltimore and Howard County mesonet sites. Precip is probably punching down to the surface.

Based off mesonet data, the wet bulb temp is 32/33 degrees for everyone west of I-95. It won't take much to bump this down below more once things get started. It looks like we might waste very little, if anything at all, on getting all frozen.

If it's a reload period with a definitive end period, that's fine. We all get worried when things just go zonal for weeks on end.

In Union Bridge already? That's great honestly. Very happy to see things going right to frozen once precip starts.

Ceilometer from McMillan Reservoir in DC showing a steady decrease in cloud heights. Precip is definitely starting to work towards the ground everywhere. https://ucn.cas.hamptonu.edu/viewer/?ceilometer=9&date=2025-12-14&minaltitude=0&maxaltitude=6200&minbackscatter=10&maxbackscatter=100000&colorscheme=turbo&log_z=1&min_time=0&max_time=60&filtermonths=0

Good to see it starting as all snow. Appears to be a bit of a warm pocket in the Frederick Valley.

Winter Weather Advisory extended to western Loudoun County

20z HRRR is fine. Just a touch of noise.

Been saying this all day

Wow

Agreed. Unlike other events, we have cold ground at night, and there's a fresh press of legit continental polar air coming in. The Bittinger mesonet site is already down to 27°, and the Frostburg site is down to 28°.

mPING reports of all snow in southern Franklin County. Encouraging.

Wet bulb freezing line is just west of I-95. I'm liking this storm more by the hour.

18z NAM and HRRR have some insane lift for several hours through the DGZ. There's legit upside potential for this one.

Anxious for the 00z LWX/PIT soundings this evening.

18z HRRR would be low end warning snowfall for northern Baltimore/Harford/Cecil. . . .

Mt Holly upgrading.

Same.

I think you get 3" of snow from this.

12z GFS now has a surface low off the Jersey coast, which allows precip to fill in better. Looks like 0.5" QPF line bumps back from Delaware to the Harford/Cecil County line.

That thing is the Lucy of CAMs. Always the warmest, driest model it seems.

It's a solid run for sure.