Heat Wave #2 Rest Of This Week

9pm Sunday

Back from a nice vacation this evening and heat is back as well.  We hit 94 in Portland today, which means we have just about had our “typical allotment” of 90 degree days.  We average 13 days per year at/above 90 in our area…but we’ve definitely exceeded our average 4 out of the past 5 years

90 Degree Days Summer Heat

We are up to #12 already this year with another 7 likely on the way.  You aren’t crazy, we HAVE seen a string of hot summers starting in 2014.  Of course 2016 was only a bit above average but it has been ridiculously hot otherwise.

We had a nice cool down Wednesday through Saturday after that 7 day spell of hot weather:

High Temp Last 13 Days

As of this evening, it’s our 4th hottest July on record in Portland, 10th hottest in Salem.

Why such hot weather?  As mentioned in previous posts this month, upper-level heights have been running quite high compared to normal.  A strong upper-level ridge is centered right over New Mexico right now, which isn’t all that unusual for July.

Jet Stream Forecast 2017

This chart shows the big ridge, centered far to our SE (the lines, not colors).  But most important for us are the warm colors showing that even well away from the big ridge heights are far higher than normal in the Pacific Northwest and British Columbia


It stays there most of the week but then edges closer to us, centered over Nevada/Utah next weekend.

Jet Stream Forecast 2017_2

That’s why I’ve put in temperatures near 100 again for next weekend.  We’ll see how that plays out.  Most important, the ridge stays nearby and keeps us continuously hot all this work week without any sort of good marine push to bring us cooler ocean air.

Models have been in great agreement showing this pattern.  Check out the ECMWF ensemble 15 day forecast surface temps at Portland:

KPDX_2018072212_eps_min_max_15 (1)

That’s a long hot spell, but you also see some sort of pattern change arriving about the middle of next week (we hope!).  Just as August arrives the ridge seems to want to weaken…maybe.

By the way, my family and I just spent two days at Waldo Lake…hadn’t been down there in almost 10 years.  That’s the 2nd largest lake in Oregon and typically real chilly, but perfectly clear.


We got lucky; the heatwave has warmed up the surface to at least 65-70 degrees, maybe even a bit warmer along the edges.  What a beautiful place with no motors and so peaceful as well.  Mosquitoes weren’t horrific, but definitely around.  As always August is better at Cascade lakes mosquito-wise.  Then we spent two nights at Clear Lake…getting pretty low early again this year.



Won’t be much left in a few weeks up there, I was almost able to walk across the wide section.  So many beautiful places to visit but just not enough time!…maybe in retirement.

Chief Meteorologist Mark Nelsen

23 Responses to Heat Wave #2 Rest Of This Week

  1. Mike says:

    I was working clearing trails (High Cascade Volunteers) in the south Waldo area last weekend, Mark. Lot of mosquitoes along the shore, but thankfully not too many inland. It’s wilderness away from the lake except on the east shore, so we must use two man crosscuts.

  2. Roland Derksen says:

    Comparing the mean daily temperatures of July 2018 with 2015 in my area, I see we are still -2.5F cooler than July 2015, up to the 23rd. However, the month’s not over yet. This could end up being almost as warm as July 2015. (but I think the July 2015 record will still remain).

    • Mike says:

      We seem to be cooling off in the evenings a bit faster than most summers. Could be my mistake, but it is not so hot in the evenings like it was in July 2015 anyway. I remember Oregon used to be like that in the 80’s. It would cool off so nicely at night.

      We have already lost about 45 minutes of daylight since the longest day of the year on june 21st.

  3. Tyler Mode in Battle Ground says:

    Not bad in Battle Ground with a low of 53.5 this morning.

  4. Jason Hougak says:

    Those 70 degree days were amazing last week

  5. alohabb says:

    Awesome weather. Keep on coming 90’s! Cause in no time will be wishing it were sunny and warm again.

    • W7ENK says:

      My sentiments, exactly!

      THIS is why I survive 8 months of dark, damp, cold, gray, dreary, crappy, cloudy, rainy, wet and windy weather every year.

  6. Boring Rain says:

    Wow, what has our climate come to?

  7. JohnD says:

    Managed to summit “Middle Sister” (of “Three Sisters” fame) this past weekend. A bit “technical” as compared with “South Sister” (and for sure “North”!)
    But not bad for a “growing older” guy!
    Calm at the summit at 10,000+’ elevation and a 15,000′ freezing level’
    Simply beautiful!

  8. Leanne Ritchey says:

    Hi Mark! On the ‘”question mark” today, Monday. You said the ocean temperature was determined by convection………I thought it was the “California Current”?

  9. Jason Hougak says:

    Hope ya enjoyed your trip Mark
    Installed both of the water well hand pumps at Clear Lake years ago.
    53 here this morning. Was a great night sleeping outside with my daughter.

  10. Paul D says:

    You summed it up nicely with “ridiculously hot”. This is getting old. 😦

  11. Muxpux (Castle Rock) says:

    Teenagers today are going to grow up thinking it never rains on the 4th and that we have hot summers.

    They’ll be the ones claiming the ice age is coming in 10 years when suddenly we have 5 straight rainy 4ths and don’t hit 90 until late July.

  12. Ken in Wood Village says:

    I’m going to guess we break 2015’s record for most 90+ degree weather this year. First 😒😉

    • Tanis Leach says:

      If I had to personally guess, I would say 35 days is not out of the question. Assuming the next 8 days are 90+, that will be 20 and we have August and September to go.

    • Paul D says:

      I would be surprised if we don’t. We haven’t even got to August yet! 😦

      • Ken in Wood Village says:

        I was thinking the same thing. Plus, if we count the week (7 days) to the 12 days we already have then that’s 19 already. We just need 10 days to tie and 11 to break the record. I hope I’m wrong (I really don’t like this HOT weather) but the way this year is going I wouldn’t be surprised 😒♨️🌡

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