The D.C. region is in for another summer heat wave, with Monday the first of at least three consecutive days likely to top 90-degree highs and humidity sending heat indexes soaring to near or over 100.
“June felt more like May until just a few days ago, and now it feels like July,” StormTeam4 meteorologist Chuck Bell said. “The heat and humidity that rolled in Saturday, and then hung around yesterday, will be here in full force until at least Thursday, when rain chances will go up and temperatures will go down.”
Summer steaminess surging. Rain chances receding. Get ready to sweat it out if you spend much time outdoors this week. Heat Index close to 100° Tue & Wed afternoons. High rain chances later this week will finally help take the edge off the temps. Favorable forecast for fireworks pic.twitter.com/Yls7Ako0Gq
— Chuck Bell (@ChuckBell4) June 28, 2021
Monday’s highs reached the low 90s with a heat index nearing 100 degrees, with high humidity lasting through the afternoon. Thunderstorms are possible along the Interstate 81 corridor in the Shenandoah Valley, but the chance of rain for the larger D.C. area is only around 20%.
Despite the brutal heat, some residents are still getting outside and are prepared for D.C. summers.
“This is Washington in the summer,” said Joe, who was walking his greyhound near Observatory Circle on Monday. “We can have variable weather. Last week was wonderful and you know the rest of the summer is going to be hot until probably mid-August.”
The same warm and muggy weather will repeat Tuesday, with daytime highs expected to reach 90 to 95 degrees, and the heat index again nearing 100 degrees.
But Wednesday is expected to be the hottest day of the week, with temperatures nearing 100 degrees in downtown D.C. — and that’s before taking the heat index into consideration, Bell said.
While the chance of rain will be 30% on Wednesday, by Thursday that increases to 60%.
“A cold front will try and breakdown this ridge of heat later in the week. These summer cold fronts have a tendency to slow down as they come east, so there is a little uncertainty on whether it arrives Thursday or Friday,” Bell said.
Thursday’s temps should be at least in the low 90s with thunderstorms hitting the area by evening.
The cold front will likely produce some storms throughout Friday and Saturday with afternoon highs reaching the low-to-mid 80s.
“The first look at the forecast for fireworks on Sunday, July 4, is favorable … until then, stay as cool and hydrated as you can,” Bell said.
Monday: Hot and humid, highs 88-94 with a heat index nearing 100 degrees. Isolated storms in the I-81 corridor. Warm and muggy Monday evening with a low of 70-76.
Tuesday: Mostly sunny, hot and humid with highs in the low-to-mid 90s. Heat index near 100 degrees.
Wednesday: Increasing clouds, hot and humid with a high of 96 degrees. Downtown D.C. could see temperatures reach 100 degrees. The heat index is expected to reach 100 degrees. Evening thunderstorms.
Thursday: Mostly cloudy, cooler, with temps in the high 80s-to-low 90s. Chance of rain is 60 percent. Thunderstorms are likely.