Through tonight: Shorter days are helping keep this heat from being even further above average. Temperatures fall quickly after sunset toward the mid-40s to the low 50s downtown and around the Chesapeake Bay. Patchy areas of dense fog may develop in the early morning, but skies are generally partly cloudy. Winds are light to calm.
View the current weather at The Washington Post.
Tomorrow (Monday): Still warm and a bit stagnant, as high pressure continues to sit over us. After any patches of fog, mist and low clouds burn off in the midmorning, we may again see some hazy sunshine. This could hold temperatures back a little, in the upper 60s to low 70s. The sunniest spots may again see some mid-70s.
Overall, it is bright, but there may still be some air pollution hanging around. Besides this downside, it remains a decent stretch of weather for outdoor activities. Light southerly breezes help mix and clear the atmosphere a little in the late afternoon.
A rundown on the reduced air quality in our region
Notice any eye, nose, throat or lung irritation today? Thanks to high pressure sitting in place over our region and absorbing surface pollution sources, some suboptimal air quality has developed, starting Friday.
Pollutants have gotten trapped at the surface recently, and we may need another day or two to clear out this stagnant air. Many spots are experiencing haze and air that just doesn’t feel good to our bodies. In some places, it’s the worst air we’ve seen in our region since July 4, the last time we had fireworks!
Winds start increasing a bit Monday night, which could help mix and stir the atmosphere so that our air near the surface is a bit cleaner. (Rains expected midweek will help wash things out, though.)
What’s compromising our air quality? We’ve had small but constant contributions to surface pollution recently. Stagnant, calm air accompanying high pressure that’s simply sitting over our region has kept an atmospheric lid on our air. Smoke has come from recent fireworks, fire pits, fireplaces, construction and industrial sources — along with automobile pollution.
It’s especially bad overnight when there’s no sun to stir and mix the atmosphere. Pollution can then hang out near its source, at Earth’s surface.
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