Despite current temperatures hovering just above freezing — dew points are currently hovering in the lower 20s and evaporation cooling will likely cause surface temperatures to drop during the PM rush, allowing for a period of moderate to heavy snow or sleet to fall across the Metropolitan Area.
The latest high-resolution rapid refresh model (images below courtesy WxBell) paints an interesting picture for those of us snow-starved DC Area residents. The image below begins at 20z (3pm) and continues through 7z (12am). Notice the dark blue representing heavy snow, orange (sleet) and pink (the dreaded freezing rain).
Most models depict the snow and sleet to break out in earnest between 3 and 6pm, just in time for the afternoon rush hour.
Temperature profiles in the mid-levels of the atmosphere are tricky today and snow or sleet could easily accumulate this evening especially along and north of the interstate 66 corridor in Northern Virginia and along and north of the route 50 corridor in central Maryland. The image below is from the latest High Resolution Rapid Refresh (HRRR) model and shows that there is at least a potential for an inch or two of snow even in the immediate Metro Area (to include the District).
Before you celebrate, keep in mind that sleet (frozen rain drops that bounce) may steal the show this evening preventing the coveted winter wonderland scene of wet snow coating everything. However, if snow ends up coming down instead then DC could pick up their first inch of snow this evening before the change over to sleet/freezing rain and eventually rain. For those of you in upper NW Washington — you have the better chance of seeing an inch. For those poor souls that chose to live in Crystal City — you get what you pay for “the urban heat island from hell”.
Total Sleet Accumulation Potential:
Some sleet is likely before the change over from snow to freezing rain.
Freezing Rain Potential
The boundary layer should warm above freezing for all liquid to begin falling during the overnight hours. This will set up the nasty freezing rain (liquid that freezes on surfaces that are at or below freezing) situation, especially across the sheltered valleys well to the north and west of the interstate 95 corridor where a quarter inch of ice is likely on trees and power lines. A glaze of ice is even possible along the interstate 95 corridor from Fredericksburg to DC and across Charles county Maryland before temperatures begin rising into the middle to upper 30s by Tuesday morning.
All the forecast ensembles continue to keep the next coastal storm well south of our area on Wednesday night into Thursday. For those of you dreaming of actually seeing winter during winter, nature will deliver you a cold slap in the face instead. Yes literally gusty winds and highs near 35 is what you get instead.