5:15 p.m. update There are no warnings currently in effect, but the storm moving through Fairfax is intense with very heavy rain rates of around one inch per hour. The storm cluster extends east into the District (umbrellas out at Nats Park), but is much weaker inside the Beltway. The strong part of the storm is sliding east-southeast into Burke and should reach the I-95 corridor south of the Beltway around Lorton and Newington between 5:30 and 6 p.m. If it holds together, it will probably move into Charles County between 6:00 and 7 p.m.
Outside of this hefty cell, widely scattered and small popup storms are possible with brief downpours just about anywhere, but these should diminish down after dark.
4:35 p.m. update: A severe thunderstorm warning is in effect through 5 p.m. for storm moving through western and central Fairfax County. Gusty winds, very heavy rain and small hail possible with this cell, affecting Herndon, Chantilly, and Fairfax.
Original post (4:31 p.m.)
A typically warm and steamy August afternoon is fueling scattered thunderstorms in the region which should continue into the evening. Gradually after dark, the storms wind down. Friday brings more mugginess and another possible round of afternoon and evening storms.
Through Tonight: There’s a roughly 50-50 chance of storms this evening. An isolated storm or two could be severe with damaging wind gusts. The typical storm produces brief downpours, gusty winds, and a bit of thunder and lightning. Storm chances diminish after dark. Areas of fog are possible towards morning, with muggy overnight lows in the low 70s downtown with mid-to-upper 60s in the cooler suburbs. Light winds.
Tomorrow (Friday): Much like today, skies are partly to mostly cloudy with a 50/50 chance of mostly late afternoon and evening storms. There’s a 30 percent chance of an isolated shower or storm prior. It’s warm and humid (dew points near 70), with highs in the mid-to-upper 80s. Winds shift from the southwest to out of the north at around 5-10 mph.
Pollen: Tree/grass/weed counts are LOW. Mold spore counts are MODERATE-HIGH
Severe storms this evening? The Storm Prediction Center issued a special statement indicating a small chance for isolated severe storms in our region through this evening. There’s a bit of spin in the atmosphere which may help generate some strong wind gusts and even an isolated weak tornado, but odds are not particularly high. It has classified the region under a slight risk of severe storms but is unlikely to issue a severe thunderstorm or tornado watch.