D.C.-area forecast: Sunshine returns today with heat and humidity building through midweek.

Express forecast

Today: Becoming mostly sunny. Slight late-day shower chance. Highs: Around 90.
Tonight: Partly cloudy. Stray evening shower? Lows: Upper 60s to low 70s.
Tomorrow: Mostly sunny and humid, still a slight shower chance. Highs: Near 90.

Forecast in detail

Sunshine returns today and each day this week looks ever muggier or hotter than the day before it. Noticeable discomfort moves in by tomorrow and we could see the heat index top 100 degrees by Tuesday and Wednesday. So plan to take it easy if you must be outside in the midday heat as chances for heat stroke and heat exhaustion increase by midweek.

Today (Sunday): Overnight clouds could linger early this morning along with some patchy fog, but should fairly quickly give way to a mostly sunny day. That August sun heats us to afternoon highs in the upper 80s to low 90s with humidity in the moderate range (dew points in the mid-60s) and light winds. Just a slight chance of a late-day shower or storm. Confidence: Medium-High

Tonight: Perhaps a stray evening shower or thundershower. Otherwise humidity is on the rise as muggier air moves in. That keeps temperatures from getting too cool, with overnight lows in the upper 60s to low 70s. Patchy fog is again possible. Confidence: Medium-High

Tomorrow (Monday): Sunny, hot, and humid. The afternoon hours have a slight shower and/or storm chance, especially out west toward the mountains. Highs top out near 90 again with uncomfortable humidity (dew points near 70 to the low 70s). Winds are light from the south. Confidence: Medium-High

Tomorrow night: Skies are partly cloudy and we only get down into the muggy low-to-mid 70s for low temperatures before dawn. Light breezes from the south continue to pump in the humidity from the Gulf of Mexico. There’s a slight chance of a stray shower or thundershower. Confidence: Medium-High

A look ahead

Caution is warranted Tuesday and Wednesday as highs reach the low-to-mid 90s and head index values soar as high as around 100 to 105 under mostly sunny skies. This combination of heat and humidity (dew points in the low 70s) makes the air feel steamier and more strenuous to our bodies than the thermometer reading alone, so do find shade or A/C when you can. Showers and storms are possible, mainly during afternoon hours, including the chance of a couple of strong storms. Confidence: Medium

https://www.washingtonpost.com/weather/2021/08/08/dc-area-forecast-sunshine-returns-today-with-heat-humidity-building-through-midweek/?