9:05 p.m. update: The afternoon storms appear to have stabilized the atmosphere pretty well locally. Currently there are no showers and storms in the metro area, though it’s not impossible we see some more develop overnight.
From earlier… D.C. logged another heat wave for 2014, with today becoming the third in a row of 90-degree or higher temperatures. All that heat, plus a heaping of humidity, helped spawn the strong to severe storms that swept through during the afternoon. While those are now off to the east, there’s more storminess ahead before our weather bliss arrives midweek.
Through Tonight: With the first line of storms now off to the east, we’ve seen the atmosphere relatively stabilized. However, additional showers and storms have formed out west (they are already moving into the region). A risk for such continues throughout this evening (50-60% chance). Storms should be less intense than earlier, but any may produce heavy rain with local flash flooding possible, plentiful lightning, and maybe isolated damaging winds. The focus of this activity in the area should be from now out west through 10 p.m. or so east, but the risk of pop-ups anywhere doesn’t really dwindle until around or after midnight. With dew points of 70 or above, temperatures won’t go far. Lows only reach the low-to-mid 70s. Sticky!
Tomorrow (Tuesday): Another day, another storm threat. Thanks to a big storm system swinging by through the Great Lakes and a big high offshore, we stay in the soup for one more day. Storm timing is still a question, and it appears the worst of the severe threat will try to set up over the eastern half of the area. That said, pretty much anyone is game for heavy rain (flash flooding may become a risk). Other severe storm risks like damaging wind and perhaps an isolated tornado should focus in the I-95 and east zone as soon as midday, and into the afternoon.
Given plenty of clouds and rain around, possibly relatively early, highs should shoot for the mid-80s to near 90. Winds are from the south around 5-10 mph outside any storms. The cold front eventually moves through during the evening or overnight.
D.C. lightning: While sub-severe during its passage through the city, a storm around the start of rush hour produced copious cloud to ground lightning. Here are a few shots from within the District: