July 10th among Seattle's ''Final Four'' of original heat records

Photo courtesy: Puget Sound Clean Air Agency

July 10th has somewhat of a badge of honor in Seattle weather records -- it's home to one of the last four original record highs for Seattle.

Sea-Tac Airport's first year as the official weather records were in 1945, and of course, every temperature recorded that year is a record high and a record low. Those records fall and adjust higher/lower as the years pass and our weather goes through its expected peaks and valleys.

Now after 69 years, you'd expect those records would have been replaced, and almost all have but there are still four that have withstood the test of time and today is one of them.

The record high for July 10 is 90 degrees, set in 1945! It joins Jan. 9 (60), May 2 (87) and Dec. 4 (60) as the last original record highs from 1945.

This research came about from an error in my blog a few weeks ago when I was remarking that neither July 1 nor July 10 had ever hit 90. We hit 94 on July 1 to get rid of that statistic but it turned out July 10 *had* hit 90 in 1945. Most online records for Sea-Tac only go back to 1948 for some reason, but those "missing" three years still count and that's where the 90 from 1945 was hiding.

On the other hand, there are still seven record lows lingering from 1945: April 9 (33), April 13 (32), Aug. 1 (48), Aug. 20 (45), Nov. 7 (28), Nov. 8 (26) and Dec. 14 (18). Record lows are a dying breed in Seattle -- urban heating from a growing city keeps the region warmer at night now and makes it more difficult to reach record lows -- especially in the summer where lows under 50 degrees are exceedingly rare.