Summer can mean a lot of things. The dates to anyone can be somewhat arbitrary. Some people consider summer runs from the Saturday of the U.S. Memorial Day weekend through the Monday of Labor Day weekend. That’s been my traditional choice.
Others consider the calendar months of June-July-August. Still others may select June 21 through September 21. And in the Puget Sound region, many believe summer does not begin until roughly July 5 and runs through the end of September.
This summer, 2021, has been a dry one in Seattle. How dry has it been? Choosing the “summer months” of June-July-August, the chart below shows this is not the driest summer we’ve had at SeaTac since 1949, but it has certainly been dryer than the median summer is for precipitation. The median is about 3.11 inches of rain for that period from 1949-2021. Seattle had 2.02 inches of rain during that period in 2021. SeaTac had as much as 8.43 inches of rain in the summer of 1968. And it had as low as 0.84 inches in 1987.
What stands out about 2021 is that of the two inches of rain it received in the summer of 2021, almost all of it fell in the 4-day period from June 10-13. Since June 14, we were pretty dry for the remainder of the summer.
Figure 1. Summer precipitation time-series chart for Seattle-Tacoma International Airport, 1949-2021.
Click on chart to zoom in.
A dot plot showing the summer precipitation at SeaTac since 1949 and ranked in order from wettest to driest is shown in Figure 2. The value for the current year, 2021 is highlighted in red text.
Click on the image to expand it.
Summer Precipitation ranked, wettest to driest.
Click on image to enlarge.