Is a cool summer time a merciless summer time? If that’s the case, Taylor Swift may have to jet again to Seattle quickly. As a result of my outlook for the following couple of months suggests a higher-than-usual shot at cooler temperatures throughout Western Washington.
However earlier than native Swifties and warm-weather fans (I see you, California transplants) go berserk, let me add this essential caveat: I believe the summer time months are prone to run cooler than regular by modern-day requirements. As in, since Taylor Swift began placing out information—not since 1945, when record-keeping for the town started at Sea-Tac Airport. Because it seems, utilizing the previous decade to find out what “regular” Seattle summer time temperatures are makes fairly a distinction. Let’s dig in and see why.
At present’s cool summers: your father’s scorching summers
It’s no secret that Seattle’s summers have warmed considerably over the past 10 years—a reality typically shared all-too-eagerly by dyed-in-the-wool locals who lengthy for the times when hitting 90 levels was an aberration, not an expectation. However simply how a lot summers have warmed in such a brief timespan is reasonably surprising. Take into account this not-so-cool stat: In 1973, the typical Seattle summertime temperature (calculated over the previous 10 years) was 63.7 levels. In 2013, that quantity had risen to 65.3. And in 2023? It stood at 67.5 levels.
In different phrases, Seattle summers have warmed extra previously 10 years (2.2 levels) than within the previous 40 years (1.6 levels). The web results of all this drastic heat is that the “scorching” summers of yesteryear are cool summers by at this time’s requirements. And that’s the place the summer time of 2024 enters the dialog.
The dying of El Niño, the rise of La Niña, and what all of it may imply for 2024
From mid-2023 till lately, the Seattle climate scene was largely dominated by El Niño—the worldwide climate phenomenon within the equatorial Pacific Ocean that sometimes brings milder fall and winter climate to the Pacific Northwest. However El Niño is collapsing as we converse, with scientists estimating it’ll be toast by July. As a replacement, there’s an excellent probability {that a} La Niña will begin to take form, with NOAA predicting a virtually 70 p.c probability of La Niña circumstances settling in between July and September. La Niña sometimes has the alternative impact of El Niño on fall and winter climate in Western Washington, with temperatures normally operating on the cool aspect and substantial snow piling up within the mountains.
The lengthy and in need of all that is that the summer time of 2024 will probably be marked by a shift from El Niño circumstances to La Niña circumstances—and if current historical past is any information, this implies the deck is stacked towards below-average temperatures in Seattle. For proof, let’s have a look at a couple of current examples of Seattle summers the place El Niño gave approach to La Niña.
The newest—and possibly essentially the most related—instance is the summer time of 2016, the place Seattle had simply come out of a powerful El Niño, not too in contrast to the one which dominated the winter of 23–24. Whereas the summer time of 2016 was not with out its stretch of scorching days—Seattle hit 90 levels six instances that August—July really ran barely cooler than regular, with the town not even touching 80 till the twentieth. The primary half of September was likewise cool, with the mercury steadily failing to succeed in 70.
Now, here is the place it will get actually attention-grabbing. The typical temperature for the summer time of 2016 (June 21–September 21) was 66.1 levels—greater than 2 levels hotter than a typical summer time within the Nineteen Seventies, but almost 1.5 levels cooler than a typical summer time within the 2020s. In different phrases, the summer time of 2016 would have led to a number of griping had it occurred a half-century earlier—but when the identical circumstances had been to settle in at this time? We’d take into account it cool and refreshing.
A have a look at different current El-Niño-to-La-Niña summers in Seattle reveals comparable patterns, with most summers operating on the cool aspect by at this time’s requirements—however not by these of fifty years in the past. This consists of the summers of 2005, 1998, 1995, and 1988. After which there’s the summer time of 2010, the place Seattle’s common temperature checked in at 63.6 levels—nearly 4 levels cooler than the typical summer time at this time! Even that summer time had its share of scorchers—the mercury topped 90 levels six instances—but it surely seems downright cool in comparison with a summer time like 2022, when Seattle reached 90 levels on 13 events. In truth, at this time, the El-Niño-to-La-Niña-transition summer time of 2010 stands as Seattle’s second “coolest” summer time of the twenty-first century, topped solely by the summer time of 2001.
Anticipate a coolish summer time. Until you’ve time-traveled from the Nineteen Seventies.
The underside line? If current historical past means something, the temperatures this summer time are prone to really feel cool to Seattleites—even supposing earlier generations would have labored up a sweat in comparable climate.
Will that make 2024 a merciless summer time? That’s for all of us—not simply the Swifties—to resolve
