D.C. heat and Code Purple alerts after stormy Fourth

D.C. Code – After a sweltering, stormy Fourth of July disrupted visits to the National Mall and delayed fireworks, the D.C. area faces additional Heat Advisory and Code Purple Air Quality Alert conditions Sunday. The National Weather Service warns heat indices up to 105,

For a lot of people, the Fourth of July in the District didn’t end when the fireworks were supposed to start. Storms rolled in, visitors were briefly forced to evacuate the National Mall, and the fireworks show was delayed.

Sunday doesn’t bring relief so much as a new round of warnings.

The National Weather Service has issued a Heat Advisory until 8 p.m. Sunday, when heat index values could reach 105. The District is also under an Extreme Heat Alert through 8 a.m. Monday, with officials warning that daytime conditions could feel at or above 105. Overnight temperatures may remain near 80.

Alongside the heat, a Code Purple Air Quality Alert is in effect for the District Sunday.

The weather system isn’t only about temperature. A flash flood watch is in effect until 1 a.m. on Monday for areas in northeast Maryland, including Anne Arundel, Baltimore, Cecil and Harford counties, including the city of Baltimore. Forecasters say showers and thunderstorms are expected during the afternoon and evening.

Sunday won’t be quite as hot as some recent days, but humidity will stay high. High temperatures are expected in the mid- to upper 90s, with heat index values near 100 to 105.

During the afternoon and evening, the main threat is heavy rain and localized flooding, with the potential for a few stronger storms to produce damaging wind gusts.

The unsettled pattern is expected to carry into Monday, with additional showers and thunderstorms likely and the potential for urban flooding. Conditions should gradually improve Tuesday, though a few showers may linger early before humidity begins to ease.

The District urged residents to stay hydrated, take breaks in air-conditioned spaces, and check on vulnerable neighbors.

Tonight. scattered showers and storms are expected to linger through much of the evening. potentially winding down closer to sunrise Monday. Low temperatures are forecast between 67 and 73, with south winds of 5 to 10 mph. Forecasters warn that slow-moving storms could pose a flash flooding threat for low water crossings.

Monday brings highs of 85 to 90 with east winds of 5 to 10 mph. Temperatures are expected to return toward seasonal averages. but forecasters say afternoon showers and storms are likely. and some could be strong—capable of damaging winds and very heavy rain that could continue the flash flooding threat.

Tuesday is expected to feature scattered showers and storms, with highs in the 80s and north winds of 5 to 10 mph—part of what forecasters describe as a wash-rinse-repeat pattern, with sunshine starting out and humidity easing over the day.

Wednesday looks similar: a chance for storms with highs around 80 to 85, northeast winds of 5 to 10 mph, and morning sunshine followed by afternoon showers and thunderstorms. Depending on where heavier downpours develop from day to day, isolated flash flooding could be possible.

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