One of the most extraordinary sequences in D.C. weather history played out Wednesday and Thursday, as the region experienced record heat, severe thunderstorms, a stunning temperature plunge, snow and then sunshine. It was as if three seasons — summer, spring and winter — passed in the span of about 18 hours.
It was a remarkable bout of weather whiplash for Washingtonians.
Unseasonably warm weather kicked off the craziness. Wednesday’s high of 86 degrees shattered the previous record by 7 degrees. It was the earliest such heat ever observed in D.C. and the second straight day to set a record.
The warmth helped fuel a complex of potent thunderstorms that roared through D.C.’s northern suburbs, triggering tornado warnings. The storms toppled scores of trees and knocked out power to thousands.
They were followed by one of the area’s most extreme temperature swings ever recorded. At Reagan National Airport, where D.C.’s official observations are recorded, temperatures plunged 53 degrees between Wednesday afternoon and Thursday afternoon — from 86 to 33. That’s the largest 24-hour drop since observations began there in 1945. The only known bigger swing occurred Jan. 28-29, 1934, when the temperature fell from 65 to 11 when observations were made downtown.
Thursday’s dramatic drop in temperature culminated in a coating to 2 inches of wet snow. Previously, D.C. had never recorded accumulating snow the day after a temperature as high as 86 degrees. Even more remarkable, the temperature was still 77 degrees at 1 a.m. the same day the snow fell — the warmest high temperature ever recorded on a day with accumulating snow.
After the snow, the fickle weather pattern had one final trick. Within an hour of the precipitation ending, skies rapidly cleared and the sun burst through. Temperatures jumped about 10 degrees and, by sunset, most of the snow had already vanished.
How the bizarre weather unfolded
The meteorological March madness began as unseasonably warm air rushed northward over the eastern United States, setting scores of records. New York City had its earliest 80-degree day ever observed.
That warmth and a touch of humidity produced an unstable air mass over the Mid-Atlantic as an unusually strong cold front approached. As the unstable air combined with exceptionally strong shear, or an increase in winds with altitude, a wave of severe thunderstorms formed over the Blue Ridge on Wednesday evening. Then it surged eastward, sweeping through D.C.’s northern suburbs.
The line of storms developed a wavelike structure, with a bowing section and other portions with curved notches or indentations along the leading edge.
One of the craziest skies I’ve ever seen, minutes before the tornado warning alert blasted here near Mount Airy, MD. The wind and sky roared, was very likely a tornado very close. More pics and video to come.@capitalweather @JustinWeather @TonyPannWBAL @StormHour @accuweather… pic.twitter.com/7eOIQw9fJ4
— Scott Jacobson (@_scottjacobson) March 12, 2026
Severe warned storm in southern Frederick County #mdwx @capitalweather @wusa9 pic.twitter.com/Og4Nhpd9Tz
— Jennifer Guillot (@Jquinn25) March 11, 2026
Over Montgomery, southern Frederick, southern Carroll and northern Howard counties, the bowing section of the storms unleashed a strong surge of straight-line winds generated by the storm’s downdraft. A small pocket of low-level cloud rotation, called a mesocyclone, created the indentation. These two features are shown on the radar image below from 7 p.m. Wednesday. The circulations prompted severe thunderstorm and tornado warnings.
Once the thunderstorms cleared, the cold front followed, blasting through the area early Thursday. Winds howled, gusting over 40 mph, and temperatures dropped from the 70s into the 40s between 5 and 9 a.m. as the front passed. But more weather drama was still to come.
A persistent band of precipitation developed behind the front, connected to atmospheric processes at high altitudes. A special type of front, an anafront, developed. It formed as low-level cold air outran an additional source of rising air in the upper atmosphere.
The zone of rising air entered the region thanks to a pocket of fast-moving air in the jet stream, called a jet streak. These dynamics helped induce an area of low pressure just to D.C.’s southeast. As air converged near the low pressure area, an elongated band of moderately heavy rain developed that gradually transitioned to sleet and snow. For a few hours, that snow band, as shown in the radar image below, remained stationary.
Snowfall accumulation exceeded predictions. The snow band was so dynamic that the Global Lightning Mapper (GLM) instrument orbiting Earth captured a small zone of lightning around 2 p.m. in Anne Arundel County. Thundersnow was reported in Annapolis.
So in the space of about 18 hours, our region went from thunderstorms to thundersnow.
How much snow fell
National Airport reported 0.1 inch of snow while Washington Dulles International Airport picked up 0.6 inches.
Other regional totals included:
- 2 inches in Dale City, Virginia
- 1.8 inches in Fairfax, Virginia
- 1.6 inches in Woodbridge, Virginia
- 1.3 inches in Crofton and Olney, Maryland
- 1.2 inches in Odenton, Maryland
- 1 inch in Herndon, Virginia
- 0.9 inches in Damascus, Maryland
- 0.6 inches in Alexandria, Virginia
- 0.5 inches in Prince Frederick, Maryland
Two photos, just 17 hours apart. South of Middleburg VA at the 660 ft elevation. @capitalweather pic.twitter.com/4GuYjG6xiL
— Claude (@ClaudeCMS) March 12, 2026
National Airport’s seasonal total is now 10.5 inches, somewhat below the full-season normal of 13.7 inches. Dulles’s seasonal total is 13.6 inches, compared to a full-season norm of 21 inches.
The post Summer to winter in hours: How one of D.C.’s wildest weather days unfolded appeared first on Washington Post.
