Update: The tornado threat for the immediate DC area has diminished for now, but there is still a tornado watch in effect for parts of Northern VA, Maryland, DC and Delaware for the next few hours. There are still some rotating thunderstorms down near Spotsylvania VA moving north, roughly parallel with I-95. The DC suburbs should keep an eye on them, and they'll start posing an issue in another 45-60 minutes.
I put "urgent" in the title because this is such a heavily populated area and these thunderstorm have a long history of producing tornadoes towards the southwest. We have two areas we're looking at right now -- the first, along I-95 in eastern Prince William County near Dale City and Woodbridge (my hometown, btw), and a second more potent tornadic rotation off to the west, east of Centreville and coming directly into the city of Fairfax.
I'm posting this barebones right now to get the word out as quickly as possible. I'll fill in the diary over the next few minutes. If you live in Prince William or Fairfax Counties in VA, take cover NOW. If you live in Washington DC or Montgomery County MD, you need to keep an eye on these storms.
Here's the current radar, I've circled the possible areas with tornadoes, and the red boxes are tornado warnings.
This image is old, from about 552PM Eastern:
Here's one of the possible tornadoes, coming into the City of Fairfax right now. It is moving north-northeast, and will impact western Fairfax County as well as Montgomery County MD over the next 30-45 minutes.
This radar image is old, from about 600 PM Eastern:
Here's the other storm, with rotation following almost directly along I-95 over Woodbridge, moving north towards Occoquan, Lorton, Newington, Franconia, Springfield and the I-95/I-495 Springfield Interchange. This is rush hour in DC, not a good time for this kind of weather.
This radar image is old, from about 600 PM Eastern:
If you know anybody living or traveling in this area right now, call them and let them know to take shelter. Tell them that they cannot take shelter under a highway overpass, if they do that, they can get killed and if they block traffic, others could get killed.
2:58 PM PT: The rotation in western FFX County is crossing I-66 right now, just north of the City of Fairfax.
3:00 PM PT: WJLA out of DC is showing the tornado warnings live, with more detailed coverage: http://www.wjla.com/...
3:01 PM PT: There are reports that Louisa, VA (the epicenter of the August quake) took a hard hit from a tornado a few hours ago, with many structures already weakened due to the 5.8 a few months ago.
3:06 PM PT: The tornado warnings are no longer in effect, but don't let your guard down yet. The rotation in the PWC storm has gone away, but the one west of Vienna approaching Wolf Trap is still pretty strong.
This image is old, from about 609 PM Eastern:
3:09 PM PT: Made a title change since folks here only want to read something with "occupy" in the title. So sue me. :)
3:10 PM PT: The tornado threat seems to have dissipated for the time being, and they're just gullywashers now. There are more storms down the pipeline along and west of I-95, so we could have a repeat of this in an hour or two. I'll keep updating if there is a spinup.
3:30 PM PT: From WJLA ABC 7 in Washington DC, this is the Sylvania House in Louisa VA, built in 1746. It was damaged in the earthquake back in August, and today's tornado tried its best to do it in. Louisa just can't get a break.
3:37 PM PT: For those asking why this is happening in October, there are a few reasons. These storms are riding along a warm front, parked pretty much southwest-to-northeast across northern Virginia. Add in some wind shear and instability, and you've got rotating storms. Nothing like we've seen the rest of the spring, but serious enough to pay attention to...especially given the population of this area. (Quite honestly, if this part of the country wasn't so heavily populated, I probably wouldn't have posted this).