UPDATE, 4:15 p.m.: A strong to severe line of thunderstorms extends from central Charles county (where a severe thunderstorm warning is in effect through 4:45 p.m., including La Plata and Port Tobacco) through Spotsylvania county. These storms are producing torrential rain and may produce damaging winds. To the north and west of this line (except out towards the mountains where new storms are moving in), all is quiet (albeit very hot) and may remain that way until the cold front gets closer after 6 p.m. - and - even then - any storms may be hit or miss. We will keep you posted if/when/where storms develop.


Overview (2:20 p.m.): The Storm Prediction Center in Norman Oklahoma has issued a Severe Thunderstorm Watch through 9 p.m. for the entire Washington, D.C. and Baltimore region.

In fact, severe thunderstorm watches extend from western Massachusetts and and Connecticut southward to the Virginia North Carolina border as a cold front interacts with a record-setting hot air mass.

Impacts: Damaging winds (up to 75 mph) and dangerous lightning are the main hazards in any storms that develop. Storms that develop are also likely to produce torrential rain. Some hail is also possible.

Timing: Storm coverage and intensity is likely to be greatest between 3:30 p.m. and 7:30 p.m. (southwest to northeast), but some storms may develop before and continue after that time window. Activity should conclude between 10 p.m. and midnight, if not earlier.

What A Severe Thunderstorm Watch means: There is potential for thunderstorms that may produce damaging winds and/or hail. It is not a guarantee of severe weather.

If a severe thunderstorm warning is issued for your location, that means dangerous thunderstorms are either occurring or are about to occur and you should seek shelter.

Earlier updates

UPDATE, 3:20 p.m.: Two areas of thunderstorms have formed ahead of the main front: 1) A narrow line of storms from southern Prince George’s county to central Anne Arundel county 2) A cluster of stronger storms in central Virginia, now moving into Stafford and Spotsylvania counties and Fredericksburg. Severe weather has not been reported so far, but heavy rains, lightning and gusty winds are likely with the storms in these two areas. The activity is slowly shifting east, northeast.

For areas north and west of these two areas of storms (much of metro D.C.), a few isolated storms may develop, but we may need to await storms associated with cold front to move in after 6 p.m.