Radar & lightning: Latest D.C. area 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.

10:10 p.m. update: The severe thunderstorm watch has expired. But scattered thunderstorms have popped up across the area along with the more solid area of heavy rain and lightning in Prince William County now moving northeast into Fairfax County. Pretty much anyone can expect the chance of a thunderstorm coming through over the next couple hours. Currently there are no severe storm warnings in effect locally.

9:25 p.m. update: The severe thunderstorm watch was extended until 10 p.m. for the immediate metro region, probably due to some vigorous storms tracking towards the region from the southwest. They’re currently edging into southern Fauquier and central Prince William counties and may try to move northeast into the metro area over the next 90 minutes. If they hold together (an open question), some downpours and lightning are possible.

6:15 p.m. update: Storms have largely dwindled across the area early this evening, though isolated activity remains. The only severe weather in the region is near the WV/Va. border and east of the bay. However, storms have still been firing up off to the west and short-term modeling suggests they may move this direction during the remainder of the evening. So, we’ll need to watch for that as the evening progresses.

HRRR hi res model showing isolated to scattered storms still in the area at 9 p.m. tonight (Weatherbell.com)

Lastly, D.C.’s official high temperature today was 99 degrees. That’s the warmest of the year so far, and warmer than any day in 2013. It’s right around where we usually top out for our hottest temperature of the year in recent history.

High heat and high humidity have helped pump up some powerful storms across the region. That’s a trend that continues into the evening, though they may continue to be hit or miss. With a slow-moving front still well to the west of the region, more storms are likely tomorrow. Oh yeah, we got to at least 98 in D.C. today, the hottest we’ve seen all year! Ugh.

Through Tonight: Scattered storms should continue across the area into the evening. The main focus through 7 p.m. should be to the west and north of I-95. With time, and before weakening after sunset, hit or miss storms could work into the rest of the region. For the most part, severe weather is isolated with this activity, and the main threat is damaging wind gusts. Copious lightning and heavy rain is also likely with any storms. Everything should calm down as we get into the late evening through midnight period. Lows eventually reach the near 70 to mid-70s range under partly cloudy skies.

Tomorrow (Thursday): A slight risk of showers or thunderstorms in the morning turns into showers and thunderstorms likely by midday into afternoon. It’s a good bet there will be higher coverage of storminess compared to today, and a severe weather risk will continue, mainly focused on isolated damaging winds. Lightning and heavy rain are also a threat, and some flash flooding is possible as time goes, especially in any slow-moving activity. Highs should reach at least the mid-and-upper 80s, perhaps into the low 90s if we see enough sun. The shower and storm risk may continue into the night, particularly the I-95 area and southeast.

See Dan Stillman’s forecast through the weekend. And if you haven’t already, join us on Facebook and follow us on Twitter . For related traffic news, check out Dr. Gridlock.