8:00 p.m. update: For the immediate metro area, the worst is over – though we may see some scattered showers and maybe a rumble overnight. The storms are now focused on the area from roughly Dale City to Waldorf and will continue dropping east-southeast affecting Fredericksburg and Southern Maryland over the next hour or so. Those areas can expect heavy rain, some gusty winds, and frequent lightning as the storms pass.
This will be the last update unless new warnings are issued for the immediate metro area. We’ll post any additional storm news in our Twitter feed above. Scroll down towards the bottom of this post for the outlook into Wednesday.
7:45 p.m. update: Storms have dropped south of Rt. 50 and are now centered in Manassas, Springfield and Clinton, sliding east-southeast. They continue to be very heavy rain and frequent lighting producers. There have been reports of isolated flooding due to the heavy rain rates (see our Twitter feed) and at least one report of a tree down in Arlington. Storms are headed towards Quantico, Fredericksburg and southern Maryland.
A severe thunderstorm warning has been issued for southeastern Prince George’s and northwestern Calvert counties until 8:30 p.m. This storm may produce damaging winds.
7:20 p.m. update: Severe thunderstorm warning for Manassas, western Fairfax County, central Fauquier County, southern Loudoun and northwestern Prince William County until 8 p.m. Storm near the Plains moving southeast at 25 mph towards Haymarket, Manassas, and Centreville. May contain wind gusts from 40-60 mph, and small hail.
7:15 p.m. update: A severe thunderstorm warning has been issued for the District, Alexandria, Arlington and western Prince George’s County until 7:45 p.m. Storm may produce wind gusts in 40-60 mph range. Frequent lightning is likely.
7:10 p.m. update: Intense storms are pushing east-southeast from Centreville and Manassas. These continue to be prolific lightning producers and producing very heavy rain and gusty winds. There are no warnings currently in effect, but best to stay inside away from windows as these pass through. These storms will move into our southern suburbs, including Manassas, Burke, Mt. Vernon, Dale City, Clinton, and Waldorf over the next 30-60 minutes.
6:45 p.m. Update: Storms, some strong to severe, have been mainly concentrated across the northern half of area thus far, but should advance into southern portions during the next hour. It looks pretty stormy around Nationals Park for the time being — and indeed the game is officially delayed by rain — but we might see a break or at least lighter rain over the ballpark after approximately 8 p.m.
6:25 p.m. Update: Severe thunderstorm warning for eastern Montgomery, southern Howard and far northwestern Prince George’s counties until 7:30 p.m. We have intense lightning with these storms, plus quarter-size hail is possible.
6:10 p.m. Update: Strong storms now moving east across much of Montgomery County are *heavy* lightning producers, along with heavy rain, gusty winds and reports of hail. This graphic shows the heavy concentration of recent lightning, both in-cloud and cloud-to-ground.
5:50 p.m. Update: A Severe Thunderstorm Warning has been issued for east-central Loudoun and western Montgomery counties, as well as the far southern tip of Frederick County and far northern tip of Fairfax County. Quarter-size hail is possible with this storm as well as damaging wind gusts in excess of 60 mph.
From 5:15 p.m. … Storms are likely this evening in many areas, a few of which may be severe with high winds and hail. The weather gradually quiets down overnight. Wednesday is a touch cooler than today, but another rounds of showers and storms is a good bet in the afternoon.
Through Tonight: Showers and storms developing in the northwest part of the region should gradually press southeastward. These storms are likely to contain very heavy rain and lightning and may also produce isolated damaging wind gusts and some small hail. The most likely time for strong storms is between 6 and 8 p.m. The chance of storms is around 60 percent. Some areas may get passed over or split by storms.
After 9 p.m. or so, most of the intense activity moves off to the southeast and/or dissipates. However, widely scattered showers may still cycle through into the pre-dawn hours. Towards sunrise, a little fog is possible, with lows 62-67 (suburbs-city).
Tomorrow (Wednesday): Variably cloudy in the morning and a bit muggy, with a slight chance of showers (20 percent chance). Showers and – possibly – thunderstorms are likely in the afternoon. I can’t rule out a strong storm or two, with highs in the low 80s. Winds shift from out of the west to out of the north at around 10 mph as a front pushes southward through the region.
Pollen: Tree count is in the HIGH range at 304.47 grains/cubic meter. Grass pollen is also HIGH at 51.12 grains/cubic meter. Weed pollen is LOW at 0.32 grains/cubic meter, which is more moderate for local area weed pollen counts.