Forecast Discussion
Friday, February 16, 2024 3:28PM EST
Winter Storm Warning in effect for the Greater Washington DC metro region from 5PM EST Friday afternoon until 6AM EST Saturday morning.
Blizzard Warning in effect for the Greater Washington DC metro region from 6AM EST Saturday morning until 9AM EST Sunday morning.
Wind Chill Advisory in effect for the Greater Washington DC metro region from 2AM EST Sunday morning until 9AM EST Sunday morning.
High to Extreme Impact Winter Weather Event will commence across the region this evening.
Clouds have overspread the forecast area with the first reports of light snow/snow flakes coming in around Charlottesville. Temps currently hover around 28-32F across the region w/ dewpts in the low 10s. The snow will spread northeastwards over the area over the next several hours probably reaching the District of Columbia between 22-23z (5-6pm) and Baltimore as well as the MD/PA line by 1z (8pm) or so. Temps will fall into the mid/upper 20s areawide as the atmosphere wetbulbs. Snow will become heavier and northeasterly surface winds will increase throughout the night as the strong southern shortwave and associated surface low move east out of the NC mountains and towards the coast by dawn. Temperatures will remain fairly steady in the mid to upper 20sF throughout the night. However, with NE winds gusting up to 35 mph as dawn approaches, wind chills will drop into the lower teens.
As the surface low approaches the VA/NC coast a powerful northern stream shortwave dropping in from the northwest will phase with the southern system leading to 1.) The surface low slowing down and veering NNE over the mouth of the Chesapeake Bay and 2.) Explosive deepening of said surface low. As this occurs snowfall rates will become very heavy (potentially exceeding 3”/hr) owing to strong lift and upper-level divergence. Winds, which will have northerly component by then, will become strong to perhaps damaging at times, gusting 50 to 60 mph (perhaps to around 70 mph at times over the Bay) particularly by the late afternoon and evening hours. This will lead to near-whiteout conditions over the region throughout the day and into Saturday night. With the strong dynamics in place occasional lightning/thunder is possible. Temps will slowly fall from the mid/upper 20s during the morning into the lower 20s by late in the afternoon dropping windchills well into the single digits.
The surface low will most likely bottom out in the upper 960smb range around 03z-06z Sunday as it stalls or possibly does a small loop around Ocean City, Maryland before moving slowly off to the east as a strong, large north Atlantic low coupled with a strong Greenland high (strongly -NAO pattern) keeps the storm from quickly heading NE. Near-whiteout blizzard conditions will continue through the night and into Sunday morning until snow starts tapering off from west to east later Sunday morning. Temps during this time will fall from the lower 20s/near 20F into the mid-teens as colder air wraps in behind the low-pressure center. With winds remaining very strong through the night. Windchills values will drop to around 5F or so below zero across the Greater DC/Baltimore metropolitan regions. Wind Chill Advisories will likely be needed across the majority of the forecast area Sunday morning.
By the end of it all snowfall totals will generally be in the 32”-48” range across the region w/ localized areas that end up under the heaviest banding the longest getting 4+ feet. Snow totals will be most likely end up around 20”-30”+ in eastern MD near the eastern shore of the Chesapeake Bay. The higher elevations far north and west may end up with 36 to 52 inches w/ localized amounts of 5+ feet possible. Snow drifts may end up as high as 20 feet in some spots. This will make travel impossible for most for a period of time after the snow has ended, especially with temperatures remain below freezing for the entire upcoming workweek.
Forecaster Wannabe: George BM