Cliff Mass on Seattle heatwave: ‘It won’t be like 2021’

A heatwave, arriving earlier than most in recent memory, is expected for Seattle and western Washington this weekend. But UW professor of atmospheric sciences Cliff Mass is dampening the record-breaking expectations.

“It won’t be like 2021,” Mass told Jason Rantz on AM 770 KTTH. “It’ll get warm. It’ll be above normal, but it’s not going to be 100 degrees.”

Mass claimed Friday will be in the mid-70s, with the days starting to get warmer in Seattle starting on Saturday as it reaches 83-84 and Sunday being a few degrees hotter. Monday, Mass said, should level out in the mid-80s, with the possibility of the day reaching 87-88 degrees.

Breakdown of records set during Washington’s 2021 heat wave

“We’re not going to get more than 90 degrees anywhere near the water in Seattle, or Bellevue, or anything like that,” Mass said.

In northwest Washington, in areas including Everett, it’s expected to be much cooler, with temperatures only reaching the 70s at the highest during the weekend. The southern and more inland areas are where the warmer temperatures are reported to be on tap, with Oregon’s Willamette Valley, and Portland specifically, set to reach the low 90s.

Eastern Washington will feature the highest temperatures in the state, but Mass does not expect the weather to hit 100 throughout Washington.

“In mid-May, it is extremely frequent to get some kind of heatwave,” Mass said. “There’s one unusual thing that may happen. The winds may pick up in eastern Washington over the weekend, and we may even see a dust storm there, so that’s something to look forward to. That’s kind of an unusual event that I think we might see.”

Spring thunderstorms sometimes bring wind events that pick up dust from agricultural fields, creating dust storms, according to the state’s Department of Ecology, typically occurring at the end of March or early April. Climate Central analyzed data from the National Oceanic and Atmospheric Administration, according to KING 5, which produced a study showing increased thunderstorm potential across nearly the whole state of Washington with a more drastic upward shift around the region — including a flurry of lightning strikes that occurred last week in the Puget Sound area.

“I should note that we perfectly predicted the 2021 heatwave a week before, so we can predict these events skillfully,” Mass said. “So with worries about deaths and injury, the faculty can tell people that it’s coming. That’s a very potent tool for dealing with things if there’s a lot of talk about climate change. Our ability to predict extreme weather really knocks down the number of people that are vulnerable from climate change, which is interesting.”

How does WA mountain snowpack water supply look this year?

The National Weather Service issued an excessive heat watch on May 10 that lasts through 8 p.m. May 15 for this upcoming heatwave. But Mass believes excessive heat, while a danger in itself, is not among the most dangerous weather conditions in the state.

“More people die from cold waves than heatwaves, and then around here, the heatwaves can cause people to die of cold because a lot of people go into the water in irresponsible fashion,” Mass said. “There’s always a few deaths in the cold waters in our region during heatwaves, so that’s something people have to watch out for.”

Listen to the Jason Rantz Show weekday afternoons from 3 – 7 p.m. on KTTH 770 AM (or HD Radio 97.3 FM HD-Channel 3). Subscribe to the podcast here.