Another wave of scorching temps in Western Washington

We're not out of the woods quite yet when it comes to highs in the 90s! In fact, Seattle could skyrocket to 93 degrees on Thursday. Thankfully, this wave of hot temps looks more short-lived than other stretches of blistering heat this summer. 

Highs today are forecast to reach the low 80s. Many backyards in Puget Sound and the Cascade valleys and foothills start flirting with the 90s tomorrow. By Thursday, highs could soar to near triple digits over the Cascade valleys (e.g. Morton, Darrington and Concrete). Thursday, the South Sound will also see highs reaching the mid 90s.

Because of the heat, the National Weather Service has posted multiple alerts across the state. For the areas in orange in the map below, Heat Advisories are in effect: that's where we're tracking a medium risk of heat-related illnesses. In the pink, Excessive Heat Warnings are in effect: those areas have an even higher threat for heat exhaustion and heat stroke. 

These alerts are posted Wednesday through Friday in Eastern Washington. Here in Western Washington, the advisory and warning continue Wednesday into Thursday night. 

Along the west slopes of the Cascades, the Excessive Heat Warning is in place for locations below 2,000 feet.

Remember to drink plenty of water this week! Make sure all the kiddos, seniors and pets in your life are staying as cool as possible. Unfortunately, the sweltering heat will make for rough sleeping weather for folks without A/C. If you don't have air-conditioning at home, I'd recommend heading into a building with A/C (e.g. a library, mall or movie theater) to help your body cool down. 

Take extra care to not start fires this week. We're staying dry for at least the next seven days, and our landscape is drying out rapidly. 

There may be a little haze from wildfires in our skies at times midweek, but Puget Sound Clean Air Agency doesn't expect a drop to air quality at the surface. For more information: https://pscleanair.gov/

New records for daily highs are possible at Sea-Tac Airport and Olympia on Thursday. Bellingham and Hoquiam will likely fall shy of any records, but we'll let you know if that changes. 

This is why we're forecasting such toasty temps this week: a dome of hot, dry air will build into the Pacific Northwest into Thursday. By Friday, that high pressure system shifts east as low pressure approaches from the west. This next upper-level system will drop highs Friday in Puget Sound to the low 80s. This increasing westerly flow will also give us rounds of morning clouds followed by afternoon sun.

Even though the low 80s will feel much more comfortable this weekend (though considered still too hot for many), we'll stay above-average through next Monday. The normal high this time of year is 78 in Seattle. 

If we hit the 90s Thursday, we'll tie the record at Sea-Tac for the second most 90-degree days in a year (the last record was set back in 2018. Historically, we average four 90-degree days at Sea-Tac, so this summer has been unusually higher than that.


Take good care this week!

Warmly, 

Meteorologist Abby Acone
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