People talk to me about the weather....and several have told me that the winds this summer have been unusual.
Last night, I gave a talk at a local paragliding club, and many of their members thought that northerly winds (from the north) were stronger and more frequent during the past month around central Puget Sound.
And tonight I discussed the issue with one of the leaders of Sand Point Sail on Lake Washington. He was also convinced that the northerly winds were stronger than normal this year.
Surely, we have had a drier-than-normal late spring and early summer in western Washington: have the winds been unusual as well, and if so, why?
This blog will reveal the answer.
The tool I will use is called a wind rose, which shows the frequency of winds by direction and speed range.
Consider the wind rose at Seattle Tacoma Airport for June 1 to July 16. The wind speed ranges for each direction are color-coded. The distance from the center tells you the frequency. Winds from the north occurred a bit over 15% of the time. Southwesterly was also a popular direction.
We can compare the wind rose from this year (again June 1- July 16) to the average wind rose for the same days of the year, but based on the climatological record over decades (1948-2025).
It is shown below.
They were right! The normal situation is to have less frequent northerly winds and more frequent southwesterly winds.
Considering the wind roses at Paine Field, Everett, in the North Sound, for the same late spring/early summer period (below), we note way less southerly winds this year than normal, but stronger northerly winds.
So, folks were right! More northerly winds this year in western Washington.As long as we are considering wind roses, let's take a look at the coast--in the case of Hoquiam.Western winds dominated this year from June 1 through today. Almost no winds from the east for the last 1.5 months.
Average, or climatological conditions at Hoquiam for the same period are also dominated by western flow, but there is far more occurrence of winds from the southwest and less from the northwest (see below).So this late spring/early summer period is a bit different than normal regarding winds over our region....but why?I think I can answer that. Below is the difference from normal of sea level pressure for the same period (June 1-mid July).
Higher than normal sea level pressure to the west and north of our region. This will tend to cause stronger than normal northerly winds and drier than normal conditions.
There is no reason to expect that this pattern has anything to do with global warming.
How do I know this?
Because climate models driven by increasing CO2 and methane do not produce this pattern.
I have carefully examined the climate model runs and my group has been running regional climate simulations as well.