Hottest Summer On Record Produces Another Heat Wave This Week

8pm Monday…

I was on vacation last week and part of the previous week, but back in the forecasting saddle this week. What has changed? It’s been hot, except for a brief cool down Friday-Sunday. And a “big” .03″ rain fell at PDX, ending our 51 day dry spell

Yesterday our own Jeff Forgeron (meteorologist on Good Day Oregon) married his best friend of 13 years under comfortable temperatures, low humidity, mainly sunny skies, and no smoke. A perfect afternoon for a “weather” wedding; Jeff nailed the timing, avoiding all the weather issues. Congrats Jeff & Katie! Here’s a nice pic of the weather team from Brian; the best team we’ve ever had!


I’ve just gone through the numbers, which are stunning:

  • #1 hottest summer on record at Portland, Salem, Eugene, Medford, Redmond, & Pendleton

This includes June 1st through August 8th. IF we have a cool 2nd half of August, that could knock us out of 1st place. For many stations, the previous “hottest summer” was 2015. Redmond’s previous hottest was 1968. Notice this includes BOTH stations where we’ve seen urban heating and others with little/no land change around the stations. This isn’t just about growing urban areas turning warmer (Example: Portland airport). We are living through a historically hot summer.


  • Portland’s 5 hottest summers? All recent (in order too): 2021, 2015, 2018, 2017, 2009
  • Salem has a longer record that goes back to 1893. Hottest years are the same: 2021, 2015, 2018, 2017, 2009
  • Salem has seen 31 days at/above 90 so far; by Friday the new record should be 35 days there.
  • Pendleton is a bit different. The 5 hottest: 2021, 1967, 1961, 1958, 2015


Portland has only seen 3.80″ rain since March 1st. That’s 5.5 months! If that happened every year, we wouldn’t have green trees all around us. That tells you all our vegetation is very stressed, and of course fire danger is extreme throughout the region. This is the driest we’ve ever seen during this period. BUT, down at Salem, over 6″ has fallen. Still well below normal, but “just” 10th driest. Pendleton has only seen 1.34″ during this time = driest on record like Portland.


Here we go again, just like in June (but not as intense); a strong upper-level ridge is developing just offshore. That means a dome of very warm air. Here’s the forecast for tomorrow; a 598dm ridge is highly unusual (again) at this latitude

Then by Thursday it flops in over on top of the Pacific Northwest. At this point 594dm heights cover much of the region. This is major heatwave territory from June through mid-August.

Now this model (WRF-GFS) quickly pushes a much cooler trough overhead Saturday and Sunday for dramatic cooling. Others keep the heat through Saturday; I think that’s a more likely outcome. Temperatures are forecast to peak around +25 to +27 (Celsius) Wednesday through Friday afternoons at 850mb. This is also major heatwave territory. Remember (until late June this year), the all-time high 850mb temp was +28.2. We will be close Thursday and Friday.

This will not be a heatwave with gusty easterly wind through the Gorge or into the western lowlands or OR/WA. That means two things. First, we won’t get as hot as we might get with a gusty east wind (106-108). And the coastline will remain reasonable, no hot east wind out there. Most likely even the north coast remains at/below 85 degrees this time around. You can see the weak/flat “thermal trough” straddling the western valleys and Cascades Thursday afternoon. This means no onshore cooling breezes, but no east wind either.

With all this in mind, we’re going for three days at/above 100 degrees Wednesday-Friday.

In reality, we could end up with just (1) 100 degree day. Why? First, Wednesday we might end up at “just” 98-99. Second, fire smoke is a big issue the 2nd half of the week. Even just a moderate smoke layer overhead could easily keep us in the 90s Friday. NASA’s GEOS-5 smoke modeling shows lots of smoke over the region Friday afternoon/evening

There are numerous small/moderate size fires burning in several complexes on the west slopes of the Cascades. We can assume they will burn more vigorously this week with heat and instability. As the upper-level ridge moves over/east of us Friday, that opens up southerly flow, bringing smoke north. Here’s the view this evening:

That’s it for now; I’ll be working most of this week. Make sure you follow me on Facebook and Twitter for more frequent updates there: Twitter: @marknelsenKPTV and Facebook @marknelsenweather

Chief Meteorologist Mark Nelsen

69 Responses to Hottest Summer On Record Produces Another Heat Wave This Week

  1. Anonymous says:

    Is summer over yet? I’m ready for fall where our heatwaves then shouldn’t get above 85.

  2. Evan -- Cedar Mill says:

    This is now an annual occurrence in Portland. Sad that we continue to poison our earth.

    • Zach says:


    • Andy says:

      I guess you weren’t alive when we had massive field burning years ago…Almost everyday in August and part of September we had choking smoke here in Albany. We were the grass seed capital of the world…

  3. Evan -- Cedar Mill says:

    Much hazier now. Smelling the smoke…

  4. Anonymous says:

    Air quality worsened substantially in the last hour. Smoke has definitely accumulated at the surface. W7 probably feeling bitter about that right now I’m sure 😀

  5. Evan -- Cedar Mill says:

    Wow, euro gives us another heat wave next week. Insane if that verifies…

  6. Evan -- Cedar Mill says:

    Honestly kind of scary that we can reach 104 even with a westerly surface flow and some haze. Definitely not normal for Portland although after the June heatwave maybe this is the new normal?

  7. Weatherdan says:

    96 at 1:30PM. Should top out around 106. Better than 45 and rainy any day. Hey Mark When you said the hottest summer in Redmond was 1968 did you mean 1958? Because 1968 was a cold and wet Summer in Salem. Peace.

  8. Anonymous says:

    Air Quality Index at 92 currently in Salem, so there must be smoke getting to the surface. I wonder how much of that will creep into Portland

  9. Evan -- Cedar Mill says:

    Probably would have hit 108 if we had easterly flow and no haze. Just absolutely shocking that we could have broke the previous record twice in the same summer during two separate events. Unprecedented almost.

  10. tim says:

    Smoke keeping temps down a bit in seattle, forecasted high of 96 most likely will not happen.

    • Joshua Lake Oswego says:

      No such ”luck” here. PDX +3 from yesterday at noon on the way to 105.

      ”Luckier” still, looks like we’re back up to 100 late next week after a very brief cool down to normal temps.

  11. Evan -- Cedar Mill says:

    NWS forecast:
    Widespread haze after 11am. Mostly sunny and hot, with a high near 104. Heat index values as high as 110. Light north northwest wind.

    Yikes heat index up yo 110. I guess we are paying for that NW wind.

  12. snomanski says:

    The sun is getting lower. The days are getting shorter. Inshallah!

    • yigablademaster says:

      The sun didn’t fully illuminate my window till 6:45am! 😲🙃. It was still rather dark at 5:30am!

      • tim says:

        Morning clouds would make it dark until 6 am but we don’t get that anymore due to climate change instead it’s 24 hours of clear skies now.

  13. tim says:

    Looks like another warm up by the middle of next week after a brief cool down although nothing like the current heat.

  14. Anonymous says:

    NWS Portland says there’s going to be widespread haze tomorrow and Friday to keep the Portland metro area below 100, can anyone verify if that looks like it’s going to be the case?

    • yigablademaster says:

      Cooler tonight already then last night at this time: Stayed above 70 or right at until 4am then briefly got to 68F but now it’s already 69 several hours earlier. and the night isn’t old yet! (knocks on wood)

  15. Evan -- Cedar Mill says:

    Both pdx and hillsboro hit 102. If there is no smoke/haze 105 is a lock for tomorrow.

  16. Anonymous says:

    104 in Hillsboro, 105 in Banks. That’s toasty. South and East Metro seem to be right around 100.

  17. Evan -- Cedar Mill says:

    The lack of east wind us keeping temps down, but it is also making dew points more uncomfortable.

  18. Ryan Lounsbury says:

    Just realized I posted my comment on the wrong thread…

    Anywho, the GFS as been underperfomring the last 24-36 hours for 850mb temps. The Euro is also peaking around 24C… If we get any sort of smoke in the mid/upper level atmosphere we may only come away with 1 day over 100.

    Both Euro and GFS lean into trough to kick off next week… At a minium we are out of this by Sunday.

  19. Weatherdan says:

    97 at 2:35PM. Compared to 117 not bad at all. Peace.

  20. Gene says:

    In light of the recent discussions on this blog about extreme heat and the changing climate in our area, I thought this might provide some interesting context about the way things used to be around here, weatherwise. While cleaning out some old files, I came across this old calendar called “the Great Oregon Rain Calendar 1979.” For each month there were some clichés presented about Oregon weather, including the following: “You can tell when summer is near in Oregon . . . the rain feels warmer,” “We had a mild winter in Oregon last year . . . but that’s understandable, it came in July,” “If you can’t see Mount Hood, it’s raining . . . if you can see Mount Hood, it’s just about to rain,” “One winter in Oregon it snowed and covered all the rain . . . the following summer it rained and melted all the snow,” “Last year in Oregon we had a total eclipse of the sun . . . too bad no one saw it.” My, how times have changed!

  21. W7ENK says:

    As I said a couple of weeks ago… bookends.

    Now, if only we could get an epic, season-ending thunderstorm outbreak to cap off this Summer of brutal hot extremes!

  22. Anonymous says:

    Wow! Hot! Speaking of, Anne is an ummmm attractive individual. Yep, sure is gunna get hot.

  23. Lurkyloo says:

    Congratulations to Jeff and Katie!!

  24. Andrew says:

    On the subject of extremes and looking ahead, seems like we’re fairly overdue for a potent fall storm. we’ve had some moderate activity in recent years but i don’t recall a true damaging storm in oct-nov for several years. It also feels like we’re due for a true arctic air incursion. We certainly got a blast of cold last february but that more or less devolved into a very surface level east wind event after showing initial signs of something more northerly and arctic (plus the late season surely moderated temps a bit). I’d be shocked if we don’t check at least one of those boxes over next 6 months, albeit that’s based purely on speculation and feel versus hard science. Extremes aren’t just reserved for summer after all.

    • W7ENK says:

      We’re due for a lot of weather things, people mention this every year. I hope we’ve checked off about all the things we’re going to get for the year already. This was the year we got to check off a new all-time record high. February had the worst ice storm in 40 years. Last year had the worst wildfire smoke in history.

      I’d like to think that’s about enough of the extremes for a while, though with Climate Change in full swing, they say such extremes will become even more extreme and more frequent. Had I said back in March that we would absolutely shatter our previous all-time record high of 107 — and in JUNE no less — by nearly 10 degrees, folks here would have laughed me off the blog, Mark might have banned me permanently and called for the psych ward to come pick me up… but here we are. So I’m with you on this Andrew, to an extent.

      We’re overdue for another CDS, which requires a nearly impossible level of precision to achieve, but so does a max temp of 116 at PDX. So does nearly 2 inches of accumulated ZR. And so does a 90+ mph downslope East wind event over the Cascade Crest at the exact peak of an extremely critical fire season, with fires and smoke over the WV so thick it literally blots out the sun and keeps the streetlights on all day. The cherry on top is all of this occurring while we’re into our second year of a deadly virus pandemic. The only things missing from this list (to date) are a volcanic eruption, a major earthquake with tsunami, and an asteroid strike. Though in all fairness, none of those things are exactly weather caused/related.

      Point being, we’ve been through a lot of uncharted territory over the past 11 months. I’d appreciate a moment to pause so we can collect ourselves before the onslaught continues, but part of me thinks we’re not going to catch that break, so fasten your seatbelts, this ride could get a little wild…

      • OC550 says:


      • Ryan Lounsbury says:

        I would suspect tht we will continue to break climate norms going forward. We are into new territory when it comes to the Earth and climate. Summers will continue to be hotter than we grew up with, winters more odd than usual with ice, snow, and even dry/sun.

        It’s a new era and it isn’t better.

        • Andrew says:

          Yeah great perspectives all! I also agree Ryan that evolving weather trends won’t always equate to the more notable extremes. A long relatively dry and mild stretch in say January where we hit 60 degrees, would constitute its own type of “extreme” but hardly trigger a general reaction. One thing that seems plainly obvious is weather prediction (distinguished from model-aided weather forecasting) is becoming harder and harder. wet winter, dry winter; hot summer; mild summer. it’s so difficult to know what’s going to happen. In all fairness, that’s always been the case but the volatility seems so much higher now that we know how much farther we can go in every direction.

  25. Weatherdan says:

    90 at 3:00PM. This is number 33 for 2021. NWS has us with the next 5 over 90 as well. Then after a brief cool down it looks like more days in the 90,s after that. The thing is next Summer might be even hotter than 2021 and so on and so on. My Mother used to say “It’s a mighty mean bird that s***s in it’s own nest. But that’s what we are doing to our planet. Keep cool, stay safe and peace.

  26. tim says:

    6-10 and 8-14 outlook keeps us above normal temps and below normal precip unfortunately but since it’s august I guess we shouldn’t expect anything else, our endless summer lives on.

  27. Mike says:

    I moved to Eugene in 2013 after 37 years in Tucson. I have heard a lot about what summers apparently were like here, but that has not been my experience. By 2017 (the drought really kicked in starting that December) there was a year’s rainfall deficit. We have now had a second year’s deficit since then. Caltopo maps show past and present fires, and it’s astounding what has burned since 2000. I’ve been in the 8 Lakes Basin area of the B and B fire, a lot of Taylor Burn, and they are not at all coming back 18 and 25 years out. As a newcomer, I get a very different view of this area. Summer is the best weather? You’ve got to be kidding. When the NWS starts saying a major heat wave isn’t going to be as bad as an historic totally beyond any records one 6 weeks ago, you know we are in trouble. Still, this week at one point 110+ had a 15% probability and 115 had a 1% probability.

    The PNW, like a lot of places, is in trouble. As a newcomer, I see it clearly. My SIL wrote, “I used to worry about what we were going to leave the next generation. Now, it is here.” I am childless, old, with no skin in the game, but I still care.

    • OC550 says:

      Thanks for your perspective Mike. It is no doubt a troubling situation and trend.

    • Hank says:

      1% chance of 115? 115 Is impossible to happen in august even if we got the most perfect set up ever 111 112 or just maybe 113 is the warmest we could get, but in this heatwave 115 is not possible, not even around salem (the part of the valley with most heat potential) could get to 115 in august, so my point is, saying 115 is a 1% chance is very unrealistic, we dont have strong enough uv, or long enough days this time of year.

    • runrain says:

      As a friend of mine often says, I’m glad I’m an old person.

  28. Roland Derksen says:

    We’re in for another round of hot weather over the next few days, but I’m predicting (at least for those of us in the northern section of the PNW) a heavy rainfall around the 20th-21st. That’s quite a few days ahead, I know, but I was right last time, so I’m trying again! 🙂

  29. Mountain Man says:

    It was interesting watching the smoke roll across the 4000+ feet ridge directly too and very çlose to my East (hikable distance) a week ago. Please don’t let it mix down here this time!!!
    I received .53 inches of rain Fri/Sat and it made it a whole 2 inches deep into my garden soil in the unwatered areas. And it’s already gone. Dust under that to about 6 inches and no run off. I’m near the western base in the foot hills of Mt Rainier if you don’t know my posts by the way.
    My stream with endangered resident cutthroat trout that have survived there for centuries are about to die. Just a trickle of water and a whole section is running dry, disappearing into the rock. That’s never happened to suck magnitude. I actually just ran a hose from the well-house over there 400 feet a week ago just in hope I can help them live.
    I drove my dad down to Vancouver for treatment today, he was stunned by all the rusty dead branches on most of the fir trees, said it feels apocalyptic. Never seen anything like it in his 80 years. Says all those trees, a lot are gonna die.
    What a summer! What in the hell!!! I guess a drought year is normal, that is what anyone would say. It is a little different this time though.
    This is pretty extremely extreme and extensive…

    • Jason Hougak says:

      I went camping 4 days on the east side of the Cascades near the Three Sisters and Broken Top. A stream on the edge of camp was tricking when we got there last Thursday. By Friday it was not flowing and Saturday it was strewn with dead Brook Trout. A few small puddles were choked with numerous Trout. The birds were having a feast on them. I’ve never seen a stream disappear so fast.

  30. W7ENK says:

    Yuck. I’m done with this HOT crap! 🥵

    Can we at least come out of it with a massive thunderstorm outbreak? Pleeeeeeease?!?

    • Mountain Man says:

      Yeah I’m with you brother, like a crash, bang boom and a downpour, I’d love that. Had that late August early September 2019. I’d like that!!! I actually had about 5 inches in two weeks then. Maybe it’ll happen again.

      • Garron Slocum says:

        Another over achieving day for forecasted temps. I think the overnight lows will break the august record of 69 for the highest, low will be blown out of the water over the next few days.

  31. Paul D says:

    It’s official: worst summer ever.

    Until next year….

    • Mike says:

      Yep. So, why is this the best season of the year?

      • Gene says:

        Because you can do stuff outside! Barbecues, ball games, gardening, bike rides, swimming, outdoor dining, golf and tennis, yardwork, etc. Yes, these have been a challenge at times during the hot stretches of this particular summer, but our outdoor conditions have been mostly good (like the four weeks in July between the historic June heat wave and the one we’re experiencing now)

  32. Anonymous says:

    I’m guessing it means surface level smoke this time? I remember after the fires last year, all of my vegetables had this awful smoke taste, especially the tomatoes. I think I’d rather have the 105 degrees for a day personally, but then again I’d rather people not die from another heatwave.

    Honestly with what happened last year and now the heatwaves n smoke this year, I think I’m going to skip gardening next summer and just buy my produce from the farmer’s market. I’d probably end up spending way less anyway

    • W7ENK says:

      No, models do not show smoke at the surface. It’s all aloft, if at all. Vertically integrated smoke model shows nothing at all over PDX, flow aloft is N-NNW, coming on slightly off the ocean. Surface winds are E-ly, but all the smoke over there blew off to Wyoming and Colorado today, so… 🤷🏼‍♂️

  33. Anonymous says:

    Thanks, Mark! It’s looking like it might not be as hot as it was looking like it could be. Here’s to hoping for only one day of triple digit weather and this being the last heatwave until next year.

  34. paulbeugene says:

    Anyone want some extra tomatoes? They’re so good this year

    • Romy Benton says:

      Boy, sure wish I’d planted some melons and okra. This would’ve been the rare ideal season for those crops.

    • Hank says:

      The tomatoes are good for people in eugene…. Here in salem most tomatoe plants died during the heatwave since it was 106 then 114 then 117, thats a tomatoe killer, but in eugene it was only 100 and 107, even though 107 is hot, its not 117 hot.
      But atleast you get to enjoy them, just dont forget to ship them to salem! Enjoy your tomatoes if you read this!

      • Hank says:

        But atleast our water melons are good! im going to harvest my first watermelon this summer next week!

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