Mid week will feature a transition to seasonably cool weather, but not before one more humid day. As we are averaging over 4 degrees above normal for September so far, I think most will welcome this change.
Today and TonightShowers, late-day clearing.
Much of the day will be cloudy with showers and perhaps a thunderstorm. It will be breezy and humid with some clearing possible during the late afternoon or evening. Areas that remain overcast or mostly cloudy will struggle to reach 80. Areas that receive more sunshine, mainly to the south and east, will reach the mid 80s to near 90. The cold front responsible for the clouds and showers will cross the region this evening and bring with it a much cooler and less humid air mass. Overnight lows will dip to the upper 50s to mid 60s.
Wednesday will be a great September day. It will be sunny with crisp blue skies, a light breeze and low humidity. Afternoon highs will be in the upper 70s to low 80s. Refer to Jason's forecast
for the rest of the week and weekend.
The above map shows temperature anomalies for Summer 2007, the United States' 6th warmest on record dating back to 1895. In addition to the very warm weather out west, we were on the border of a second area of extreme departures centered in the Ohio and Tennessee valleys. See more on our summer below. Image courtesy of NOAA.
For the 3rd year in a row we had a hot summer. DC finished with a 3 month average, 1.3 degrees above normal. However, unlike the past 2 summers which were wet, we finished with only 7.25" of precipitation for the summer, making 2007 our driest since 1998. We have had 41 90-degree days to date, slightly above our normal of 37. Dulles Airport (IAD) really heated up this summer from the dry conditions. IAD finished with a summer average 3.1 degrees above normal for their warmest summer on record, just squeaking by 1993 (records date back to 1963). Dulles only recorded 6.34" of precipitation this summer for the 3rd driest on record and the driest since 1983. Normally averaging over 3 degrees cooler than DC for the summer, IAD was only 1.5 degrees cooler this summer and featured a staggering 47 90-degree days. To each his own, but I say bring on Fall.
Tropical Update - Humberto?
As Tropical Storm Gabrielle
moves quickly away from the east coast toward the northeast, keep your eye on an area of development that is still well east of the lesser Antilles. This wave is expected to organize and strengthen and could become Humberto over the next few days. It is still at least a week before affecting the US, if at all.