The Inland Northwest is likely to see a cold and snowy winter this year under a weather pattern similar to 2007-’08, when La Niña brought near-record snowfall.
“We are certainly going to have more of a winter than we had last winter, which is a no-brainer,” said John Livingston, meteorologist in charge of the National Weather Service bureau in Spokane.
Livingston said the U.S. Climate Prediction Center is calling for the chance of colder-than-normal temperatures in December, January and February along with higher amounts of precipitation.
That should translate into more valley snow this year, he said.
A La Niña cooling of tropical waters in the Pacific has allowed higher air pressure to build into the North Pacific, causing cooler air and low pressure systems to circulate southward along its leading edge.
That pattern, which has been present for weeks, is likely to continue through autumn and into winter, Livingston said.
La Niña began to emerge in May and replaced an El Niño warming of the tropical Pacific last winter.
Warmer tropical water allows the jet stream to swing to the south across the Pacific, sending milder air onshore. La Niña has roughly the opposite effect.
Livingston said he does not expect a repeat of the near-record snowfall in 2007-’08 or the record snowfall the following year, but the region should see more than Spokane’s 30-year average of 45 inches.
Spokane set a record of 97.7 inches of snow in 2008-’09; the year before the region had 92.6 inches.
Last season’s snowfall was the third-lowest on record, at 13.7 inches, and the least that has fallen at Spokane International Airport since record-keeping was moved there in 1947.