Spring is drier than normal in the Pacific Northwest

Today I had to water some new plants because the past few weeks have been relatively dry. So I’m curious…..how dry is the weather in our area?

Below is the rainfall from March 22 to April 12 in Seattle over the past 75 years. This year we had 1.5 inches during a time when 2.5 inches was more common.

This was not a record dry year as there were some years with only about 0.3 inches during the same period. Interestingly, early season springs have become slightly wetter over the past 75 years, so one cannot blame the dryness on global warming.

Another reason you can’t blame global warming is because right up the coast, southern California is experiencing one of its wettest springs on record. To demonstrate this, look at the rainfall totals from March 22 to April 12 in Los Angeles during the same period (below).

It’s been a very wet year and many things are normal.

To give you some spatial perspective, below are the percentages of normal rainfall over the past month.

Much wetter than normal in southern California (blue and purple), but drier than normal in western Oregon and Washington. Very humid in Arizona.

This pattern, dry north and wet south, is associated with a persistent atmospheric pattern this winter and spring, with a strong low pressure trough off California.

The higher forecast level (pressure 500hPa, about 18,000 ft) shown at 5pm today—exactly what I’m talking about. A strong low perches over California.

For those hoping to save on water bills, the forecast for rain through Thursday morning is similar. California is wet and there are a few light showers in western Washington and Oregon.

I’m completely bored with this.