100 Degree Heat In Willamette Valley Today; One More Hot Day to Go!

9pm Tuesday…

Whew…today was a scorcher, especially for so late in the summer season.  Let’s go over the numbers…

Several spots in the Willamette Valley hit 100 degrees, the hottest temps of Summer 2019.  Salem, Eugene, Aurora, and down in Roseburg too.

Todays Observed Highs OrWa 2017

Check out those coastal numbers!  Upper 80s to upper 90s throughout the FOX12 viewing area from Yachats to Long Beach.  When wind remains offshore through 1-2pm those temperatures can soar all the way down to the ocean beaches.

You can see we hit 98 in Portland, a new record for August 27th.  This also tied the highest temperature of Summer 2019 set in early June.

Hottest Days This Year

I had mentioned over the past 5-6 days this would be a classic late summer/early fall east wind event; it sure did deliver!  In one hour from 9:15 to 10:15 am Tillamook’s temperaure jumped 23 degrees! (63 to 86).  At PDX it jumped from 81 to 91 in one hour between 11am and Noon.

Easterly wind gusts made it to 52 mph at Vista House.  That’s pretty strong for late summer.

For the geeks, the 850 millibar temperature made it to 24.4 degrees on this afternoon’s sounding.  That’s right up with the big late summer heatwaves.  In fact during a ten-year period 1999 to 2009, only one P.M. sounding (out of 300+) had a higher temperature!  That day it jumped to 102 at PDX; likely earlier in the month.

What’s ahead?  Temperatures should just barely drop to 60 in the city by sunrise, and into the 50s outlying areas.   That’s thanks to nights two hours longer than a June or early July heatwave.  Areas that continue to see the easterly breeze (near Gorge and higher hills) may stay in the lower 70s.

Mark Forecast Night City Temps

Tomorrow the hot thermal trough (area of lowest pressure) shifts east of the Cascades late in the day.  That cools the coastline, but we’ll still get up to between 95-99 degrees in the metro area.  Another scorcher, but without the hot wind.

A weak upper-level disturbance passes overhead tomorrow night and early Thursday.  The ECMWF and WRF-GFS (UW) continue to insist showers pop up with this during that time.  The 18z ECMWF brings a swath of showers across NW Oregon and SW Washington through the first half of Thursday.


A bit wetter than other models though.  We’ll see.  Regardless, don’t leave anything outside tomorrow night just in case.  Of course temperatures will drop at least 15 degrees (or even 20) Thursday due to morning clouds/showers and a push of marine air.  Should be refreshing.

Beyond tomorrow we settle into a typical late-summer pattern of morning clouds and afternoon sunshine.  Labor Day Weekend will likely see highs between 75-82 degrees in Portland with varying amounts of cloud cover.

Chief Meteorologist Mark Nelsen

27 Responses to 100 Degree Heat In Willamette Valley Today; One More Hot Day to Go!


    so any one else getting quite the show this morning?
    been mostly cloud to cloud…but once it hits the mountain ranges all bets are on for a fire or two.

  2. runrain says:

    Looks like lightning detected west of Corvallis. Also, a small dying shower near Oregon City.

  3. W7ENK says:

    In the 45 mins to an hour it took me to get home from downtown, the sky to the South went from a prickly ACCAS field, grown into a full-on storm looking sky. Clouds are definitely gathering and building, poised to move overhead soon…

  4. W7ENK says:

    A couple of un-forecast/un-modeled spots just popped in the SW Willamette Valley. One about to hit Monmouth/Dallas, the other just passed over Albany. Right on the edge of radar range (since RTX is still down).

    Anyone with eyes on down that way?? 95 at PDX currently.

  5. Andy says:

    Things are firing up in Southern Oregon heading north…however the bad news is the radar in down in our area. I guess we will be looking to the sky instead. Seems as if we have a lot of issues with our radar compared to other areas…example the southern Oregon system is rarely down. Cross our fingers for some good action.

  6. W7ENK says:

    Moisture now moving into Oregon from N. California, from just East of Brookings across Southern Oregon all the way to Lakeview. Moisture plume is pushing farther West, and is a bit earlier than modeled, both of which could bode well for the Willamette Valley. tonight.

    We shall see…

  7. runrain says:

    Quite a cloud field in Southern Oregon moving north. Hope that bodes well for thunderstorms.

  8. Joshua Lake Oswego says:

    All high res models (HRRR, NAM-WRF, WRF-GFS) are skunking us or close to it for rain through tomorrow. 18z running now for HRRR and NAM.

    • W7ENK says:

      HRRR isn’t seeing the moisture that’s already over Josephine / Curry Counties. It does show some small pops over the Western end of Lane County, moving NNE through Western Marion/Clackamas Counties later (around midnight), with some more significant pops just a few miles out from the Central Oregon Coast around the same time. More pops by 2am from Astoria up the Columbia River to about Longview-ish, and on a line extending across the Southern counties of Washington, all the way out to maybe Pendleton. Also some further development/enhancement of the pops just offshore from Tillamook & Clatsop Counties. Astoria gets several good rounds, approaching South Sound by 7-8am, but Portland Metro and the N. Willamette Valley look to be in a hole… there’s a surprise. 😦

    • W7ENK says:

      Oops, forgot to complete my original thought…

      Holding out hope that the moisture currently over Josephine & Curry Counties (not seen/modeled by HRRR) is indicative of a higher than anticipated moisture content that will provide a little extra punch for us in the N. Valley and PDX metro later.

      Wishcasting at its finest… 🤞🤞


      Reporting in from Castle Rock, Washington

      we currently have Thunderstorms moving through the area.
      and it’s been going on for 2 hours.

  9. Roland Derksen says:

    Looks like August 2019 is going out with below normal rainfall here, and it should be the 4th straight year where it had less precipitation than July.

    • Roland Derksen says:

      whoops- slight correction: 3 out of the last 4 years have had a drier August than July.

  10. Dean Suhr says:

    Mark – love reading your blog. A suggestion … on a few slow weather days it would be great if you would help more of us to “geek out” on the technical stuff. Perhaps a few tutorials on the various models, how you adjust the models based on your local experience and insight, millibars, P.M.’s, etc. , etc. These posts could become part of an archive you could refer to in the future. Or better yet, maybe a handful of “Mark’s Weather Minute” videos that you periodically record in studio with the green screen behind you to speak to the graphics and geography.

    • Kyle Hill says:

      I’ve always wanted something like Mark’s Technical Vids. That would be awesome and even cooler a 7 day forecast archive of our storms and temperature extremes to see how past forecasts fared.

    • Kyle says:

      I’ve always wanted a Mark’s technical video. Also a 7 day forecast archive to compare forecasts of the past to what actually happened.

    • Mark Nelsen says:

      I think this is a great idea but… I don’t have the time. I typically do 4 shows a day and will add another (4pm) in early September. Hopefully the blogging won’t suffer much.

  11. W7ENK says:

    Thunderstorms tonight/tomorrow between 3am and 2pm

    CAPE looks good: 8am

    Lightning looks good: 8am

    Precip looks good: 8am


  12. PAUL D says:

    Looks like we’ll make it through this year with NO 100+ days at PDX!! Woot!!

  13. Joshua Lake Oswego says:

    63.8 here at the moment. I see that some locations in the immediate metro area (SW Portland mainly) are at or above 70 degrees. Definitely not going to drop to 60 in a lot of spots.

    • W7ENK says:

      Overnight low at my place in Milwaukie was 68 degrees. That’s a bit ridiculous, considering the humidity wasn’t there to support it. Walking from the train to my office this morning, I could still feel the infrared from yesterday’s hot sun radiating off the walls of the buildings at sidewalk level.

  14. W7ENK says:

    Not sure how this is a “wrap up of our mini heatwave” when were smack in the middle of it. Today was Day 1, and tomorrow has potential to be a degree or two hotter. It’s currently 84 degrees at (almost) 10:30 at night. I wonder if it doesn’t bottom out around 72 here overnight, this Easterly breeze hasn’t let up at all. If it weren’t for the A/C in my window, this would be miserable!

    Fingers still crossed for thunderstorms tomorrow night… ⚡⚡🤞

%d bloggers like this: