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Ahead of a cold front, temperatures touched the 90-degree mark for just the third time this month at Reagan National. Between tonight and midday Friday, we could see an isolated shower (even a rumble) as the cold front moves through.  Then, we welcome dry, delightful and, ultimately, cooler air.

Through Tonight: Isolated thundershowers are possible through sunset, mostly southeast of I-95 towards the Bay (30 percent chance; 10-20 percent chance elsewhere).  For the rest of the night, it’s partly cloudy and mild, with a 20 percent chance of an isolated shower, mainly towards morning.  Lows range from 66-71(suburbs-city) with moderate-to-high humidity. Light winds from the west.

Tomorrow (Friday): We have a 20 percent chance of a shower in the morning, mainly south of the District.  Otherwise, expect partly cloudy skies and a slow reduction in humidity from north to south.  Highs are in the mid-80s, with winds coming in from the north at around 10 mph by afternoon.

See David Streit’s 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.

Pollen: Tree and grass counts are LOW, weeds are MODERATE-HIGH, mold spores are MODERATE-HIGH


Sunset over Rosslyn Tuesday (Christopher Skillman via Flickr)

50th anniversary of failed hurricane modification experiment:  Blogs NOAA’s Hurricane Research Division:

On Aug. 23, 1963, Project STORMFURY (a joint Weather Bureau/U.S. Navy hurricane modification program) carried out the first of a two-day seeding experiment on Hurricane Beulah. At the time Beulah was nearly a thousand miles southeast of Bermuda and heading north. Eleven aircraft carried out elaborate monitoring patterns as Navy A3-D jets delivered 400 pounds of silver iodide to the hurricane’s eyewall. Little change was noted and, by the second day, the hurricane reached its peak intensity.

Hurricane modification – which has never been proven possible – has a controversial past.  Read these pieces by CWG’s Steve Tracton for background:

The Hairy Issue of Hurricane Modification

DHS Rebuffed by NOAA on Hurricane Modification

NOAA Says No to DHS Hurricane Modification