Thursday, July 30, 2009

Unprecedented Heat in the Pacific Northwest!

It has been not just hot, nor incredibly hot, but never-before-recorded hot in the Pacific Northwest this week. Wednesday, the high temperature in Seattle at Seattle-Tacoma International Airport reached 103 degrees. This was the hottest temperature ever recorded on any day at the airport. Previously, the all-time hottest temperature at that measurement site was 100 degrees, which occurred on July 20, 1994.

Another measurement site in Seattle at Sandpoint climbed even higher, to 105 degrees on Wednesday! This was another new all-time record at that site, where the previous hottest temperature was 96 also on July 20, 1994.

So what's the big deal? Why all the fuss about the heat in this part of the country? Well, clearly this is unusual for the Pacific Northwest. Average high temperatures this time of year in Seattle are around 77 degrees. That is comfortable enough to go without air conditioning year-round. So many residences do not have A/C in this part of the country. That makes for dangerous heat!

Meanwhile, from the Great Lakes into the Northeast, Summer temperatures have been running below average. Here's an interesting perspective on Chicago's cooler-than-average July.

We have been about average this summer in Central Virginia, as ample moisture and the dip in the jetstream just to our west keep us from extreme heat or extreme coolness. We've had typical heat and humidity for the Summer months, with afternoon and evening showers and storms that develop almost like clock-work. For July-to-date in Richmond, our average temperature is just a degree below average, and we've had only one truly sweltering day this month when the hottest high all Summer occurred this past Sunday, July 26 at 97 degrees. June's average temperature in Richmond was about 2 degrees above average, with the hottest high reaching 95 degrees on June 20.
--Carrie