3:15 a.m. update: The National Weather Service has extended the flash flood warning for D.C. until 6 a.m. Flash flood warnings are also in effect for much of the surrounding area. The weather service said that as of 3:05 a.m., “up to 2 additional inches of rain can be expected.”

12:15 a.m. update: Storms have refused to “rain themselves out” thus far over western suburbs where official totals are now past 3″ at Dulles Airport in the last 2.5 hours. Unofficial totals as high as 4-5″ or more are possible in some spots near the Loudoun/Fairfax border already. Storms have now also developed into D.C. where a flash flood warning runs until 315 am.  Remember: Turn around, don’t drown. (flash flooding is a leading cause of weather death)

Radar with flash flood warnings shown in green as of 11:30 p.m.

11:30 p.m. update: A line of heavy showers and thunderstorms has prompted numerous flash flood warnings over western and now northern suburbs. These warnings run as late as 2:30 a.m. and may be extended if storms persist. So far, movement has been rather slow. Additional storms may pop up in other locations, or these may eventually rain themselves out. This is the type of weather we can expect into tomorrow at least at times thanks to a slow moving storm system.

Radar & lightning: Latest regional radar shows movement of precipitation and lightning strikes over past two hours. Refresh page to update. Click here or on image to enlarge. Or see radar bigger on our Weather Wall.

Most of the day has been pretty quiet around here as a front shifts just to our south while stalling out. Highs mostly made the mid-80s, with some upper 80s sprinkled in as well. Though we’ve dodged rain through much of the daylight hours, that’s not likely to persist over the next day as an upper-level system swirls near the area.

Through Tonight: Partly to mostly cloudy skies continue, but trending cloudier. Odds of rain go up as we get toward late evening and into the overnight period. Let’s call it rain likely at times, though the further south you are the better your chances for appreciable rainfall it would seem. Periods of moderate to heavy rain (with some thunder) are possible. Lows range from the upper 60s to lower 70s.

Tomorrow (Friday): Showers and thundershowers remain likely off and on through the day. Pinpointing exact timing and location will be difficult until things set up, but you should plan on bringing an umbrella when you head out in the morning at least! As with the overnight, periods of moderate to heavy rain are possible. Highs right around 80 should do it most spots, though a better range might be upper 70s to the low 80s. We might get stuck in the 70s under the rainiest scenarios.

See David Streit’s forecast through the beginning of next week. And if you haven’t already, join us on Facebook and follow us on Twitter . For related traffic news, check out Dr. Gridlock.

Midday clouds and sun. (Ian Livingston)

In the market for a weather station? The New York Times ran a cool story looking at various models and types of home weather stations that are out there. They note that personal weather stations can run from about $150 to $2,500 depending on what you want as far as bells and whistles. Read the article!

Pollen update: Tree, grass and weed pollens remain LOW. Mold spores are VERY HIGH.