Wednesday, August 8, 2007

Swinging for the Record Books: Heat on Steroids

**Heat Advisory in Effect Until 8 PM This Evening **


Sunny, record heat, humid. Unhindered by the clouds of yesterday and helped by a drying westerly breeze, the sun went to bat today chasing a long-standing temperature record. The temperature rose several degrees an hour through the morning, as much as 5° between 9 and 10 am, and by 1:03, the National Airport temperature hit 102°, breaking the record for the date set in 1930. After retreating several degrees temporarily, the temperature was back up to 101° at 4pm. Except for the 97° at 2pm, the reading at National has been at or above 100° for 5 consecutive hours.

Records were also set at both of the other major airports: at least 100° at Dulles and 102° at BWI. Several records were set or tied elsewhere in Virginia as well: Richmond 102°, Danville 100° (tied), Blacksburg 91° (tied).

Humidity is also quite high, although the 8 hours of greater than 75° dewpoints overnight were replaced by readings near or below 70° this afternoon. When combined with the hot temperatures, however, the heat index reached at least 108°. Scattered locally severe thunderstorms fired up in the early afternoon between Pittsburgh and Morgantown WV, but these have so far remained over and west of the mountains. chart from NWS data, photo © Kevin Ambrose

Tonight and Tomorrow

Hot, humid, scattered thunderstorms possible. Very warm and humid conditions will continue overnight with only a slight chance of scattered thunderstorms through this evening. Lows will be mainly in the upper 70s to near 80° in town and some mid 70s in the 'burbosphere. Tomorrow will be mostly sunny and not quite as hot with highs 93-97° and only a 20% chance of afternoon or evening thunderstorms.

For the outlook through the rest of the week and the weekend, scroll on down to Dan's post below.

Climate Corner

While today's WaPo featured the current heat wave on the front page, inside the A section was an article, "Across Globe, Extremes of Heat and Rain", about a just-released World Meteorological Organization report on recent extreme weather events throughout the globe. Although any individual weather event cannot be directly tied to climate change, widespread extremes are certainly consistent with such a scenario.

Also on today's WaPo front page was an article, "Warming Draws Evangelicals Into Environmentalist Fold", about the developing collaboration between evangelical groups and the environmental movement.

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