Major Heat Wave, High Fire Danger This Weekend

ALERT: A Red Flag Warning is in effect for the Puget Sound Lowlands from Saturday morning to Sunday night, due to low humidity and elevated fire danger. See the alert below or CLICK HERE. (It is relatively rare for us to have this alert...last time it was issued was August 2017).

In addition, the Excessive Heat Watch is still in effect. Read it below or CLICK HERE.

That’s a strongly worded alert with a good purpose...keeping us all safe. I expect this to be upgraded to an Excessive Heat Warning soon. (If this happens, I will have a new blog post...an excessive heat warning is a big deal!)

Let’s take a look at the forecast. Here’s the weather.com forecast for Puyallup. 

3 days above 90 degrees, with a peak of 100 DEGREES on Sunday. This is followed by a slow cooldown to around 80 by Wednesday. Saturday and Monday will be quite hot as well, with temperatures in the upper 80s to low 90s.

Regarding Sunday...while this forecast says Puyallup will reach triple-digits, I would expect a more likely temperature of 95-99, with a chance of 100+. The warmest areas will be away from Puget Sound and in mountain valleys. Valleys are especially hot because the hot air gets trapped down low, warming the surface.

As a side note...if it feels like we’re going to be baking like the Desert Southwest, this heat is being pushed up from that area...and heat alerts stretch from the SW to the Canadian border. Take a look at the NWS map below.

Here’s a look at the UW WRF-GFS model for high temperatures at 5 PM on Saturday and Sunday.

Saturday:

This model forecast is very high resolution...and quite accurate. It shows highs 84-90 degrees, higher temperatures away from the water and in the valleys.

Sunday: (The Big Heat)

Very hot around the area on Sunday. This model shows temperatures above 90 degrees around Puget Sound, and if you look real close you see a light shade of pink (96+ degrees) in the river valleys (including Puyallup).

Another important aspect of the weekend heat wave will be increased fire danger. This is why a red flag warning is in effect. Humidity will be 25-35%, possibly lower, with temperatures 85-100 degrees. This will promote explosive growth of fires. Do not burn outdoors or do anything that will spark a fire this weekend.

Here is a graphic from NWS Seattle showing the heat risk on Sunday. As the graphic says, heat like this happens “only a few times each year.”

Notice that parts of the Puyallup/Tacoma/Federal Way areas are in HIGH RISK. Be sure to practice all the heat safety tips on the graphic.

If you want more information about the heat, be sure to leave a comment below.