Updated Friday 11:15 p.m.
"Nearly ninety in Seattle, that MUST have been a record!", you say? Not quite. In fact, not even close. What were you doing on July 29th, 2009...? If you were here in Puget Sound, you were probably desperately trying to cool off. After a string of scorching, record-shattering afternoons, the big kahuna came on this date seven years ago: Sea-Tac Airport sizzled, bubbled, and broiled up to a whopping 103 degrees for THE. HOTTEST. AFTERNOON. EVER. recorded around here. Wow. These 80s and low 90s aren't half bad.
Another reason that they're fairly bearable is that it's a 'dry heat'. I know, I know, there's still a touch of mugginess. But with humidity readings in the 30th to 40th percentile today thanks to the warming, drying north winds, it wasn't 'knock you over' sweltering heat like you get east of the Rockies this time of year, where humidity levels can easily be double or worse what we have seen the last few days.
It's been a bit warm for sleeping at night during this kind of scenario, but we only have to handle that for another night, too. Overnight lows will take all night just to cool off to about 60 degrees downtown, although most of our homes will stay much warmer than that. It will definitely be a night for the power companies to earn their keep with all of the fans plugged in and blowing on high to help us sleep.
A big rush of natural cool air chips away at the heat Saturday. A stronger marine push will follow a weak upper trough of low pressure as it traipses across the Northwest. You'll notice several changes as a result. Early clouds will fill in around the Sound. Although they shouldn't last long, they'll serve to moderate the heat, dropping most communities back into the middle to upper 70s by the afternoon. There will be a slim chance for a thundershower over the Cascade crest, but the more noticeable change in Eastern Washington will be the gusty winds. Blows between 20 and 35 mph will rip down the eastern slopes of the Cascades, making for 2-hands-on-the-steering wheel driving crossing the Columbia near Vantage, and prompting a Red Flag Warning due to higher fire danger tomorrow in a good portion of the state from Yakima to Spokane.
It will still be terrific for Torchlight Saturday night--the parade will wind through downtown to really get the Seafair festivities going, and we'll have mainly clear skies and evening temperatures slowing dropping into the 60s after dark.
Sunday will be cooler still, again with early clouds and afternoon sunshine. Highs will stay in the middle 70s.
Early next week looks a bit dicey as a stronger disturbance moves in Monday and Tuesday. It could trigger a shower or thundershower, and highs will drop back into the low 70s beneath partly cloudy to mostly cloudy skies. We'll rebound later in the week, which is good timing with Seafair Weekend on deck.
Have a super summer weekend!
Meteorologist Shannon O'Donnell
The KOMO4 Forecast Team
Today's Record Temperatures