Disclaimer: I’m using the Metric System’s Celsius temperatures, and IMHO sticking with degrees F is yet another silly+unhelpful form of American Exceptionalism. That said, the graphs from UW are F-dominated, so they can help you figure it out if needed.
Today marks the 7th 8th consecutive day with 30+c temperatures around Portland, Oregon, and the 6th day around Seattle. Originally this PNW heatwave was forecast to last 4-5 days, but this one seems to linger on and its end date keeps getting pushed out. Not complaining about the forecast — NOAA had warned of this Heat Dome a good week in advance.
In Portland whose 1961-1990 average high for this time of year was 26-27c, it’s been >35c since Monday, with the end now possibly coming Sunday night after 7 consecutive >35c days; probably a duration record. In Seattle whose 1961-1990 average high was ~24c, the airport station crossed 30c Tuesday, and has been closer to 35c most afternoons since then. Vancouver BC is a couple steps down at ~20.5c historical average high, and seems to have gotten it easy this time around, their airport reading almost never reaching 30c. However, just look at those minimum temperatures in the headline plot! Indeed, the nights have been ridiculously warm this past week, and on this front our neighbors to the north have not been spared.
Just like Northwestern Europe which also has traditionally mild summers, and unlike most of California, the majority of homes here lack AC and are often geared more towards retaining heat than blocking it out. The traditional method of opening all doors and windows at nightfall to get some cool breeze in, has been rendered rather ineffective this week, as the night air has been mostly still and warm, cooling down very very slowly and providing substantial home cooling only in wee early morning, when most people are wary of keeping doors open. Saturday morning I woke up at 5:30 AM and it was exactly 20.0c outside (and 25.7 inside). I opened the front door to allow another degree or so of cooling before things heated up again.
And our home is cooler than most of Greater Seattle. Indeed we’re privileged in several ways:
- I previously called our location on the north face of Maple Leaf hill “The Seattle Alps”, and stand by this name. Even though our elevation isn’t very high objectively, there’s some microclimate that keep us 2-3c cooler than Seatac. During the current heatwave, every day since Tuesday our digital “mercury” stopped somewhere between 31 and 32c. Arguably sufferable (but also scary stable).
- We have a spacious home (not a McMansion though — it was built in 1947) with a daylight basement that’s substantially cooler than the main floor. So we can escape there, at least to sleep.
- We also have central fan heating (no AC) which allows recirculation between those floors, a pretty effective cooling method for the top floor at the end of the day, when one can pair it with opening windows and doors.
- We’re <10 min drive from a fabulous Lake Washington beach — that’s where we spent most of the evening on that crazy record-shattering 42c day last year, during which our home topped out at 39.3c outside and an insufferable 32c inside.
So we thought we’re relatively ready — until a big scary wrench got thrown in:
Our 23yo son who lives with us got positive with Covid Thursday morning. Goodbye air circulation and sleeping downstairs (that’s where his bedroom is), as well as hopping over to cool off at the lake — at least not with any substantial number of people there. To complicate matters, our youngest son was out all week at a sports camp, so we’ve separated from him as well since his return, b/c unlike him we were exposed to his brother before he started isolating.
Then on Saturday night my wife tested positive too, so the 4 of us ate dinner and then slept in 4 different locations. Still very privileged — I cannot imagine what a family w/Covid and far less room is doing right now in the heat. Probably no way to avoid everyone getting infected, short of obtaining a public isolation facility spot. I expect to turn positive soon too, which will at least allow me to reunite with my wife and with our bedroom :)
3 pm pdt update: aaaaand I also tested positive just now. Ugh
Still no fever and few symptoms. But my ‘T’ line was blazing strong vs. my wife’s faint line last night. Now the only (still) negative in the household is also the only minor. He’s a big boy but still, yet another wrench thrown in.
The media and most locals have been reminded this week mostly of last year’s mind-blowing Heat Dome. On June 29 2021 the temperature famously reached 46.5c in Portland, giving it Bronze Medal for 3rd-hottest record temperature among major US cities. Seattle’s 42c that day also shattered the local all-time record, it was the first time Seatac temps landed north (south?) of 40. Vancouver again seems in the plot above as if it got it easier; but even more famously, only 150 km to Vancouver’s northeast a small mountain-valley BC town shattered Canada’s all-time heat record for 3 days in a row, nearing 50c - and then promptly got burned down.
Last year’s Dome was unique not only in its intensity but in its happening in late June, usually far less warm than July-August. Perhaps that’s one reason it was shorter, lasting ~5 days and breaking rather dramatically (see plot above). On the merits, the current heatwave is far more similar to the 2009 one which took place exactly the same time of year— last week of July — and at the time, also shattered the Seattle and Portland all-time temperature records.
Lasting over 10 days, like this time around the 2009 wave’s days were scarily similar to each other (except for a slight downblip in Seattle on July 31). At the time we lived in a much worse rental house with no roof/wall insulation, and even though it did have some sort of basement it was insufferable in there too.
The thing is, these waves are not the only heatwaves each summer anymore. And this one might end up breaking very few records if any (I’m not counting daily temp records, which are only meaningful when aggregated). I believe Portland had already crossed 35c on 2 separate occasions earlier this year.
This week the weather outside felt very familiar to me — just like in Israel-Palestine where I had spent the majority of my life. Indeed, it is relatively little-known outside wonkish circles, that PNW climate is in fact a member of the Mediterranean family. Officially, a “Warm-summer Mediterranean” in contrast to the main, hot-summer one that dominates California as well as its namesake home around the Mediterranean. The two siblings share dry summers and wet relatively mild winters, but are separated both by the length of each season (Hot-Med has 5-7 months of de-facto summer, vs. barely 2-3 in the PNW), and by typical summer temps. In low-elevation locations in Israel-Palestine, low 30s is the typical daily summer max, >35c is rather routine, and even >40c occurs in most places at least once per year.
As we heat the planet, at least my simplistic expectation is that the climate-zone boundary will gradually shift northward, and we will experience more traits of our southerly neighbor/sibing climate. In particular, we will routinely see even drier and hotter summers, longer dry spells, and more violent rain/snow storms when these arrive. We’ve seen all of those increase, dramatically. I have a colleague who spent the late 1970s to mid-1990s here in the foothills east of Seattle, then returned to (cooler) Bellingham a few years ago. She said it’s almost unrecognizable.
Portland in particular, might already be acting “Full Hot Med” these past several years. Even though officially our sibling climate supposedly stops somewhere near the CA/OR border at present (see map below), The Weird City keeps logging more and more often, increasingly long summer stretches that are out of place anywhere except a Hot-Med (or Hot-Desert) zone. Our oldest son has lived in Portland since last summer, so we get firsthand testimony of the not-so-mild-anymore climate there (both summer and winter).
So that boundary is already moving. We must do our part — or rather, given our continent’s super-high footprint lifestyle+legacy, and our often sluggish and self-contradictory political climate action — stop doing the bad parts we’re doing, and really push forward the good stuff. And put it at the top of our to-do list.
Both collectively and individually. Every little bit helps.