This June was another month of mainly warmer-than-normal days and mild nights, despite the significant swing in temperature that had record highs and days of chill and gloom.
At Sea-Tac Airport (SEA), it was the third month in a row of warmer average temperature than normal. (Average daily temperature is the high and low temperature combined.)
While the airport is not in Seattle city limits, it has been the official climatological station for the city since 1945. So what happens at SEA goes in the record books for Seattle!
The monthly average temperature at SEA Airport in June was 64.0° F. This was the seventh-warmest June in the 82-year period of recordkeeping.
Believe it or not, the warmest June on record was not 2021, when we clocked three days over 100°, including the all-time high of 108° on June 28 of that year in the midst of an unbelievable and deadly “heat dome.” It turns out June 2021 is number two on the list, bested barely by the average temperature in June 2015!
Let’s go south now to our state capital...
The monthly average temperature at the Olympia Airport (OLM) was 61.1° F, tied for the 11th-warmest in that period of record, which dates from 1948.
I really like to look at the temperature records at the Olympia Airport and compare with SEA, since there has been less urbanization around that airport compared with the heavily developed area right around Seatac. The “urban heat island effect” brings some extra heating to heavily urbanized areas in the daytime and especially at night. In more rural areas, we tend to get a little better look at “pure” temperature patterns over many decades of recordkeeping — without as much strong influence from new pavement, asphalt, and buildings nearby.
But the numbers at Olympia, too, prove this was a very warm month of June!
A few of the other official climate locations:
Bellingham ended with a June average temperature of 60.6° F, tied for 16th warmest since 1949.
And Hoquiam had a June average temperature of 58.8° F, tied for tenth-warmest since 1953.
The Quillayute State Airport at Forks is another of our five official climate sites in Western Washington, but its temperature sensor was offline for much of the month.
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