Hot & Smoky Ahead; Then “Fall” Arrives

8am Sunday

I’ve ignored weather maps during my weekend, but this morning I see three highlights while perusing weather maps with my coffee.


The first is that we’ve got another brief period of hot weather coming, although once again the heat won’t be too extreme.  We don’t get long heat waves in late August and this will be no different.  Highs reach right around 90-95 or so Monday-Wednesday.  Today should be fine.  Just a bit warmer than yesterday with highs in the mid-upper 80s.  You’ll notice a little more fire smoke than yesterday, and in parts of the metro area the air quality has gone downhill again.  We’ve got weak onshore flow today, keeping those temperatures in check.  Notice the easterly flow on the cross section forecast for Tuesday.   The colored areas are relative humidity above 70%, see how the marine layer disappears Monday PM and Tuesday AM.  “21/12” on the chart refers to 5am Tuesday.  “20/12” is 5am Monday.

But later Monday and all day Tuesday we get an offshore/easterly flow coming down out of Eastern Washington, through the Gorge, over the Cascades, and into NW Oregon.  That helps things heat up Monday and Tuesday, but brings a problem back…


Yuck!  I just checked the HRRR smoke modeling and it shows smoke from all those fires in northern Washington pouring back down over us just like it did last week.  The loop is here:  Here’s the image for right now.


and then the image for tomorrow morning around 8am…you see the northeast flow has brought the smoke right down over us again.


The smoke will be with us Monday-Wednesday (3 days), then a HUGE change is showing up on all models the latter half of the week…looks like FALL!


Yes, I know it’s not technically fall but it’s the biggest change we’ve seen since late spring.  All through July/August we’ve had a semi-permanent ridge of high pressure either over us, just to the east, or just to the west/northwest.  Here’s the ECMWF ensemble average of upper-level heights for Wednesday; warmer colors are above average heights and blue are below average


and then one week from now, Sunday the 26th


A cool upper-level trough over Western Canada and the Pacific Northwest.  This screams “end of summer weather” for at least 4-5 days starting Thursday.  A thick marine layer Thursday and beyond means you’ll need to get used to lots of morning (or all day) clouds and spots of morning drizzle at times.  High temps will drop at least down into the mid 70s.  This late in the season a thick marine layer with AM drizzle can keep us in the upper 60s too.  Here’s the ECMWF ensemble meteogram for Portland; quite a change eh?


Looks pretty comfortable!  It’s not like we’re entering a cool & wet period, but the chance for showers definitely goes up at times beyond Thursday, or maybe it’s better to phrase it as “guaranteed dry weather goes away for a few days.  Notice temps do rise slightly beyond Sunday, back to normal which is in the upper 70s the last few days of August.

I’ll be back at work today (I work Sunday-Thursday), forecasting on the 5, 8, 9, 10, & 11pm shows…I shouldn’t be hard to find!

Chief Meteorologist Mark Nelsen

41 Responses to Hot & Smoky Ahead; Then “Fall” Arrives

  1. Cliff Gavic says:

    right now it’s 72 degrees in sandy, oregon.

  2. Cliff Gavic says:

    according to the NWS Portland office discussion page the cooler air and a chance of rain for oregon, mainly that chance of a wetting rain for the higher terrain, i.e., cascades. Other than that, light rain and drizzle for the coast and coastal range.

  3. Ken in Wood Village says:

    18Z GFS came out being much wetter. It will be interesting to see if the EURO does the same thing. This would be in the right direction (at least for me) to help with the fires around the PNW.

  4. W7ENK says:

    It’s definitely not going to reach 90 today in PDX. Marine air moved in overnight, which cooled us off and raised the humidity, plus the smoke is thicker overhead than it’s been all Summer so far. The combined effect is going to keep us down into the mid 80s, at the warmest. Current temperatures around PDX (KPDX doesn’t seem to be reporting for some reason) are all in the mid to upper 70s at 2pm, with only a handful of low 80s sprinkled in.

  5. Air quality improved to moderate this morning, but is now back to unhealthy levels. Visibility is down to maybe 1.5 miles here right now. Even worse east of the mountains; Spokane and Tri-Cities are reporting hazardous air quality this afternoon.

  6. Andy says:

    71 At 1:30 pm here in Albany. Probably a bust for high temps today. maybe the smoke will save Portland from breaking the number of 90s for summer?

  7. Mark S. says:

    “Taste of Fall”? More like “Taste of Normal”. Upcoming highs look to be just a few degrees below normal summer temps.

  8. Joshua Lake Oswego says:

    Don’t think we’re hitting 90 today. No complaints here. Thanks for something, smoke.

  9. pappoose in scappoose says:

    Oregon Smoke Information

  10. Roland Derksen says:

    Red sun here this morning- and it feels like early fall. The temperature here in BC has dropped because of the thick smoke.

  11. Paul D says:

    It’s time to PUT A FORK in summer!

  12. alohabb says:

    Wow. It looks horrible outside

    • K says:

      Yeah, not pleasant up here in the West Hills. Air quality is tumbling down a ravine right now.

      • Ken in Wood Village says:

        It’s not the greatest out my way either. I have to use my inhaler. Normally I don’t need to use it but this year I have needed to use it a few times because of the smoke.

        “K” not sure what models you look at but I have been looking at I zoom out and I have been looking at the temperatures up North (Alaska and Canada area) I have been noticing the temps have been steadily dropping. I noticed over on Greenland there are temps below zero.

        Could fall start sooner this year??? I don’t know but I said something about what I think could be happening for fall/winter. We’ll see if what I said comes true or not.

        How are you doing K? I don’t think I could handle all the smoke you are having up there. I can barely handle it down were I live…lol. I’m looking forward to fall/winter. I want to go up to Crown Point and experience 100 mph winds again…lol 🙂

        • K says:

          I’m doing great Ken, how are you?

          My sincere hope is that fall gets an early start. I have been chatting on the Category 6 weather forum, and some there have mentioned the possibility of an active typhoon season, which bodes the possibility of a typhoon riding the jet stream straight into us.

          Sadly, the GFS has removed the somewhat hefty rain we were supposed to get, but it’s still a while out so a lot could change.

        • Ken in Wood Village says:

          I’m doing great K. I ordered a new laptop (a gaming laptop with more RAM and a higher processer) because my current laptop is falling apart.

          I never heard about the “Category 6 weather forum” before. I may have to look into it. The GFS (and even the Euro) goes back and forth. We will have more of an idea when we get closer to those days. I still believe fall will be starting sooner this year. We probably won’t get a lot of rain at first but I believe the temps will start becoming more average to below normal. I think we won’t see extended amount of 90+ temps after this week. It’s just a hunch I have with what I have been seeing on the models. 🙂

  13. Boring Rain says:

    Watch out for smokey sub-90 shockers the next few days!

  14. JERAT416 says:

    I would love it if every day in July and August was like a 90 degree September day. 50 or below each morning, 90 by 2pm and a quick cool down again. Anyone else?

  15. JohnD says:

    I probably missed previous comments–as I am in a rush this evening; but it “appears” that PDX should “tie” the 90’+ record on Monday @ 29 days; then “beat” it @ 30 and 31 days respectively this Tues. and Wed.!

  16. W7ENK says:

    Took a day trip out to Central Oregon today, showing off the area to my neighbor and his kids (they moved here from Oklahoma a couple of years ago) who had never been out there before. Turned them all loose with rock picks to dig up thundereggs on Richardson’s Ranch NE of Madras. They absolutely loved the Oregon Desert, and we dug up some really nice geodes.

    The air was pretty clear this morning, but as the afternoon wore on the smoke rolled in really thick. Visibility dropped from maybe 30 miles (still not great) down to less that 5 by the time we left.

    Not looking forward to more days of smoky air. Thunderstorm (with decent rains) would be welcomed with open arms, but it seems those were nothing more than a fleeting thought in the back of the collective weather models’ minds…

  17. cgavic says:

    I might be selfish here (knowing the smoke and flames are out there) I live in Sandy. But the part of “fall” I do not like (on the west side) is moonscape, constant drizzle, rain, or light rain. At least in Central Oregon it may rain, but it gets it over with. No moonscape or constant drizzle or rain/heavy rain. You get to enjoy cooler temps, of course, for fall, but you enjoy crisp air, falling leaves and don’t have to plan anything around the rain. But Jesus has my sister and I (caregiver) planted in Sandy. For now.

  18. JERAT416 says:

    So anyone placing bets on whether this does a 180 again? How is this any different when it comes to the forecast?

    • Ken in Wood Village says:

      I actually thought the same thing but the models keep showing it. About a week ago I said something about this week could be the turning point with not having the extreme heat. It looks like later in the week that could come true.

      This is the way I look at it. I want to say the seasons are a little off. We started getting drier and warmer early (like spring and summer started early) so I believe fall will start early. I don’t think we will see a bunch of rain but we could start seeing temps a little below average. I could be eating crow but I have been watching how the whole year has been transpiring and this is what I believe.

      If it doesn’t happen then I have egg on my face. I will be the first person to admit I missed up if it doesn’t come true but I wanted to say my peace 🙂

    • My thoughts exactly… there was supposed to be such a change underway a week or two ago and it went bust. Here’s hoping this one turns out to be the real thing. As soon as the air gets nasty and smoky I start getting tired of summer!

      • Ken in Wood Village says:

        I’m not sure who you could be talking to but I believe we will start having a shift in the pattern now. The High is going to move west more which will allow to have a NW flow (which normally gives us cooler weather). The EURO and GFS have been showing this for the past few runs and the past few days. Hopefully this will happen. I would really like to have fall start early…lol

  19. Boring Rain says:

    No more thunderstorms early this week?

  20. Glad to see relief is finally on the way! We’re getting a nice taste of fall here in Rapid City this morning, too. Rainy, windy, and barely 60 degrees. Summer is winding down for sure.

  21. alohabb says:

    I wish summer would never leave.

  22. Paul D says:

    One more round of hot weather? You sure? It would be nice to be done with the 90’s and drop into the 70’s for more than one day!!

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