A Very Dry Thanksgiving, But No Record
There will be no precipitation over Washington State during the Thanksgiving holiday.
None. Zippo. Nada.
Which is kind of surprising since this is the wettest time of the year for our region.
To show how unusual it is, here is the climatological probability of measurable precipitation at SeaTac Airport for each day of the year. The last three weeks of November are wetter than any other period, with roughly a 65% chance of rain on any day.
But this year, there will be no rain–something predicted by virtually every weather modeling system.
For example, the European Center forecast model has nothing through Tuesday morning (see below).
So how unusual is a totally dry Thanksgiving period. Let’s find out!
I found that total precipitation at SeaTac airport for November 23-27 for every year of its record (see below). 2023 will be zero, of course. There have been several totally dry Thanksgivings, the last being 2015. About ten Thanksgivings have been dry or very, very close to totally dry.
As shown by the brown line, which shows the trend over the entire period, there is little trend, either up or down, over the period of record (since 1947)