Seattle's 90˚F Days....

August 25, 2021 David Blackwell

This summer has been pretty nice in Seattle. Aside from a few very extreme temperature days in late June, it has been a pretty typical summer. Aside from the three days in late June which exceeded 100˚F, about five (5) other days reached 90˚F, so far. The summer is not over yet. Nevertheless five days exceeds the annual average at Seattle-Tacoma International Airport (KSEA) average of about 3.3 days per year reaching 90F or higher. And adding back in the 100˚F days in late June, means we’ve had eight (8) days this summer at 90F or above, more than twice the number of hot days we see in summer. Since 2014, this seems to be the new norm though we’ve had one year since then where we reached 90˚F only twice.

Figure 1 below shows the number of days each year where the maximum daily temperature reached 90˚F or higher at Seattle-Tacoma International Airport. Click on the chart to expand it.

Figure 1. Counts of 90˚F Days.
Click to expand.