Rainy & Cool, Then Another Heat Wave with Temperatures in the 90s

The rainiest day since mid-June is likely on Saturday. Additionally, temperatures will barely reach 70 degrees (a welcome relief considering what lies ahead).

Below is the UW rain forecast through 5 AM Monday.

This shows 0.05 to 0.2 inches of rain in the Puget Sound area. Expect up to 0.5 inches on the coast and from Everett northward. The Cascades and Olympics will receive up to 1 inch of rain…greatly needed to help suppress wildfires.

The UW forecast compares nicely with the NWS Seattle forecast for rain through Sunday morning.

SeaTac Airport, the official station for Seattle, received 0.01” of drizzle late Thursday night, officially ending the dry streak at 51 days, tied for the 2nd longest ever. However, not all areas got drizzle, and at my house in Federal Way, the dry streak continues at 52 days. That will likely end on Saturday as more widespread rain moves through. 

Expect rain and showers to continue through Sunday, getting more sporadic by midday Sunday.

Now for what you’ve all been waiting for…the next heat wave. (Insert collective groan). The warmup will be gradual, with temperatures warming from the 70s to mid 80s from Saturday to Tuesday, before the real heat begins on Wednesday, as seen in the Weather Underground forecast below for Federal Way.

By Wednesday, highs reach the upper 80s, possibly the low 90s. Then, starting on Thursday, the hottest temperatures since the June heat wave arrive. Current forecasts show 3 straight days in the mid to upper 90s, with nighttime lows only dropping to the mid to upper 60s.

The hottest days are likely going to by Thursday, Friday (peak heat), and Saturday. Expect forecasts to fluctuate a bit over the next few days, so stay tuned for updated information.

This upcoming heat is going to be about 15-20 degrees above average, and the probability of above average temperatures is quite high, as seen in the NWS Climate Prediction Center outlook for August 11-15 below.

The Pacific Northwest is shaded in the maximum value on the scale, with a 90% probability of above average temperatures.

For now…enjoy a few cooler days with some rain, and be prepared for the return of heat.