The Washington PostDemocracy Dies in Darkness

D.C.-area forecast: Mugginess returns by tonight. Heat wave starts this weekend.

Only slight rain chances in the days ahead

The Potomac's Mather Gorge near the middle of Wet Bottom Chute on June 18. (huskerdont77/ Flickr)

Today’s daily digit

A somewhat subjective rating of the day’s weather, on a scale of 0 to 10.

8/10: Morning into midday hours look great but clouds, breezes, and mugginess increase with time.

Express forecast

  • Today: Partly sunny. More humid with time. Highs: 80 to 85.
  • Tonight: Clouds increase. Stray shower? Lows: 66 to 72.
  • Tomorrow: PM shower/storm possible. Highs: Mid-80s to near 90.
  • Sunday: Muggy and mostly sunny. Highs: Low to mid-90s.

Forecast in detail

Most of today is still good outdoor weather but rising dew points give us those “humid-feels” by tonight. The slightest of rain chances brings some clouds tonight into tomorrow, helping us perhaps stay below 90 degrees until Sunday — when the heat arrives on top of the humidity already in place.

Get our daily forecasts on your Amazon Alexa device.

Today (Friday): The morning into midday hours may still be superb. Slowly increasing clouds and humidity (dew points surpassing 60 degrees) return as we get into the later afternoon or evening hours. High temperatures generally top out in the range of 80-to-85 degrees. South-southeasterly breezes may be a bit more noticeable, gusting above 10 mph, by late afternoon as well. Confidence: High

Tonight: Skies may turn mostly cloudy by midnight, but you should still be able to spot the final night of the “Strawberry Supermoon.” Low temperatures cool more modestly, down toward the 66-to-72-degree range, thanks to increasing humidity. (Dew points will be as high as the upper 60s.) A stray shower or storm is only slightly possible but nothing heavy or long-lasting is expected. Southerly breezes stay under 10 mph. Confidence: Medium-High

Follow us on YouTube, Facebook, Twitter and Instagram for the latest updates. Keep reading for the forecast into next week…

Tomorrow (Saturday): Showers and storms remain slightly possible (around a 25 percent chance), especially during the afternoon. Much of the region remains dry, though, so be sure to water your plants or crops when you can. Clouds may dominate the sky more often than not. Fairly drippy humidity (with dew points near 70 degrees) has returned, but high temperatures try to stay below 90 degrees in most spots. Even so, we’re still reaching at least the mid- to upper 80s. Confidence: Medium

Tomorrow night: Clouds and any slight chance of raindrops decrease fairly quickly as the evening turns to late night. Low temperatures are quite summery, near 70 degrees to the mid-70s. Light southerly breezes can be expected. (It helps keep the air from being too stifling!) Confidence: Medium-High

A look ahead

Sunday: Mostly sunny conditions return. We could be in the beginning of our next heat wave. Highs are near 90 to perhaps as hot as the mid-90s. With high mugginess (dew points around 70 degrees) we could feel closer to 100 degrees, because our skin will be less able to breathe. Confidence: Medium-High

Sunday night: We may only get down into the low to mid-70s for predawn low temperatures. Skies are no clearer than partly cloudy, and a little bit hazy, thanks to continued high humidity (with dew points around 70 degrees). If up early, look south and you should see the nearly full moon with Jupiter and Saturn. Confidence: Medium

A steamy heat wave continues to establish itself Monday and Tuesday with 90s for high temperatures and high humidity (with dew points around 70 degrees), too. When combining these air temperatures and dew points, our skin can’t self-cool as easily, so the apparent “heat index” temperature may feel near 105 degrees in a few locations. Cooling showers and storms may be few and far between, but we have a slightly higher chance of seeing them on Tuesday compared with Monday. Confidence: Medium-High

Read more about Capital Weather Gang’s confidence rating.