Portland will see a typical mid-July day Thursday with sunny skies all day and a high of about 86 degrees.
The National Weather Service says a ridge of high pressure, building northward into the Pacific Northwest, will usher in a short heat wave that should peak on Saturday.
The weather service has issued a heat advisory that will be in effect from noon-9 p.m. Saturday warning of temperatures from 93-98 degrees in the metro area.
And Friday won’t be a lot cooler. Temperatures on Friday, under sunny skies, should reach about 91 degrees.
Those looking to escape the heat might consider heading to the coast. Oregon’s beaches will still be under the effects of onshore flow and could be about 20 degrees cooler than cities in the Willamette Valley this weekend.
Saturday’s heat advisory covers much of the Interstate 5 corridor and extends to communities east and west of the interstate including Portland, the western Columbia River Gorge, greater Vancouver, Salem, Eugene, and the western slopes of the Cascade foothills.
The hottest temperatures will likely occur across the central and southern Willamette Valley, according to the weather service, and some of those locations have a slight chance of hitting 100 on Saturday.
Relief from the heat should show up quickly on Sunday. Models are still in some disagreement on exact temperatures Sunday, but it’s possible Portland will cool to about 88 degrees by the end of the weekend. Increasing onshore flow should help the southern valley cool down quickly too. Most areas should be cooler than 90 degrees.
Forecast models are in good agreement that more significant cooling will show up to start next week. Monday could have highs in the upper 70s. And there’s a slight chance of rain in some northwest Oregon locations too, especially near the coast or in the Coast Range.
