I actually forgot about Oregon City. Their POR is hit and miss but pretty clean back to 1948. They hit 105 last year with a pre-2021 record of 108. So again, fairly close and I don't see a 3 degree difference as enough to make some sweeping case for anything. Particularly when there were corroborating stations near PDX with similar results. I think the most reasonable takeaway is that the areas down near the Columbia River had just the right amount of adiabatic help last August to give them the extra push they needed in getting to that rarified 107+ territory. Otherwise, it was generally slightly less historic 104-106F temps across the metro area. Microclimates and mesoscale features like downslope are very important when we're talking about the exact degrees of difference in a case like this. Obviously in a truly unprecedented event like June 2021, microclimates don't matter quite as much. But for a lot of our pre-2021 big hitters, you see a fair amount of spread in the area based just on mesoscale/microscale factors. For example, Forest Grove hit 108 in July 1998 when PDX limped its way to 101. And in July 1956, some timely downslope helped Battle Ground hit 107 while PDX stalled out at 102. It's pretty clear that August 2023 was in that same territory and was at least roughly on the level of any other pre-2021 heat wave peak in the Portland metro.

The good thing about this heat wave is that the hot air won’t reach the Coast. It will be a great destination for those who don’t have AC this holiday weekend.

and 1955

From Michael Synder on twitter. He missed 1941. "How rare are 100 degree days in Seattle? With the shot at a very hot day or 2 coming up this weekend let's take a look: In July of 1994, Seattle recorded its first 100 degree day in history. Then 15 years later, Seattle hit an incredible 103f (July) In June 2021 Seattle hit 100 for 3 consecutive days! Including back to back all-time records in (104f and 108f)"

Thanks for bringing up Forest Grove as well. Too bad there aren't more reliable long term stations out there. So based on what you said, we have five Portland metro stations with relatively long records (early 70s or further back) in the same location: PDX, downtown Portland, VUO, Battle Ground, and Forest Grove. Two exceeded their pre-2021 record in August 2023, and three fell several degrees short of it. Which supports the point I was making.