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We logged a relatively rare 90-degree reading this afternoon.  It was the first 90+ degree day in nearly two weeks, and 16th of 2014, about 8 below average by this time in early August.  We have another shot at 90 tomorrow, before a cold front closes the window for any more hot weather for a while.  This front may carry along some late day storms.

Through Tonight: An isolated storm or two out in the mountains may try to crawl eastward, but I’d put storms in the D.C. metro region at 10 percent or less.  For the most part, it’s a partly cloudy and warm this evening, with temperatures falling back through the 80s and into the 70s.  Early morning lows range from the mid-60s in our cooler suburbs to the low 70s downtown.  Calm winds.

Tomorrow (Wednesday): Partly sunny skies through early afternoon, and very warm and humid.  Between 2 p.m. and 10 p.m. showers and storms are possible (50 percent chance).  Some storms may produce gusty winds and heavy downpours, but any severe storms should be isolated.  Before storms roll through, highs range from 86-91.

See Matt Rogers’ forecast through the weekend. And if you haven’t already, join us on Facebook and follow us on Twitter . For related traffic news, check out Dr. Gridlock.

Contrails over Ellington at Sunset on August 4 (Clif Burns via Flickr)

Pollen: Tree and weed counts are LOW.  Grass counts are LOW to MODERATE and mold spore counts are MODERATE-HIGH.

Why Are D.C.’s Official Weather Readings Measured in Virginia? I speak to local NPR affiliate WAMU about Reagan National’s temperature readings and discuss whether an alternative measuring location is need, that would actually be in the District. Link: WAMU article and audio file.

See also these related articles I’ve written on the subject: Reagan National Airport’s misleading low temperatures | Should Reagan National Airport remain Washington, D.C.’s official weather station?