By Linda Weiford, WSU News
In its recently published “Top 10 Cloudiest U.S. States,” the periodical famous for its long-term weather forecasts and astronomy data placed the Evergreen State in first place (see http://farmersalmanac.com/weather/2015/09/14/top-10-cloudiest-u-s-states/).
But wait. Isn’t this the same state that just emerged from its hottest, driest summer on record? And doesn’t two-thirds of the state remain in “extreme drought” status? And what about Yakima, Wash. – the city so sunny that it is nicknamed the “Palm Springs of the Pacific Northwest?”
“Yes, a section of Washington is one of the cloudiest regions in the country, but there’s more to the story than our cloudy coastline,” said Washington State University meteorologist Nic Loyd of AgWeatherNet, a WSU network of 166 weather stations statewide.
Unfortunately, the No. 1 rating fuels the misconception that all of the state is draped in leaden gray, he said.
“Washington’s weather is more diverse than perhaps anywhere else in the country, and there are some big differences depending on which part of the state you are asking about,” he said. “We do have rainforests and lots of clouds, but we also have arid and semi-arid deserts and plenty of sun.”
Cloud cover and sunbeams
The ranking appears to be based on a single segment of the state, said Loyd. Due to the Pacific Ocean’s moist air, the west side experiences ample cloud cover and rain, mostly during winter months. Even so, “we’re only talking about a third or so of the state,” he said.
The other two-thirds comprise central and eastern Washington, where places such as Yakima, the Tri-Cities, Walla Walla and Spokane see far less precipitation and fewer cloudy days. The 10,000 foot-high Cascade Range that bisects the state from north to south is responsible because it hampers the flow of moist air moving eastward from the Pacific, said Loyd.
“This is largely why, east of the Cascades, the term, ‘cloudiest’ is not an accurate depiction,” he said.
Consider this: Quillayute, located on the state’s northwest coastal rainforest, gets 239 cloudy days and 104 inches of rain annually. By contrast, Yakima gets 164 cloudy days and only 8.2 inches of rain, according to the Western Regional Climate Center.
Even coastal weather can vary in surprising ways. Take the drizzly town of Forks, Wash., the backdrop of the best-selling “Twilight” vampire romance series. Each year, it receives an average of 120 inches of rainfall.
Yet a mere 70 miles away, clear-skied Sequim averages just 16 inches. Nicknamed “sunny Sequim,” it is located in the rain shadow of the Olympic Mountains, just as Yakima is in the rain shadow of the Cascades, explained Loyd.
“When it comes to our climate, we’re fortunate to have something for everyone – the best of both worlds – cloudy rainforest and sunny deserts and everything in between.”
Nic Loyd, WSU meteorologist, 509-786-9357, firstname.lastname@example.org
Linda Weiford, WSU News, 509-335-7209, email@example.com