The U.S. Climate Prediction Center reinforced Thursday that Washington can expect a winter similar to last year’s, which led to one of the state’s worse droughts on record.
A powerful El Nino dominates the three-month outlook by the center, a branch of the National Oceanic and Atmospheric Administration.
The El Nino, a warming of the Pacific Ocean, is the strongest since 1997-98. It’s expected to peak in November and December and gradually cool off by May, according to forecasters.
Primarily because of warm sea surface conditions, NOAA forecasters predict Washington has at least a 60 percent chance of exceeding normal temperatures in November, December and January. The forecast suggests long odds for a winter that would replenish snow-dependent reservoirs and rivers over next summer. This was the first three-month forecast to include January,
“The tropical Pacific is as warm as toast,” Washington State Climatologist Nick Bond said Thursday. “I think we can say with just a little bit additional confidence it’s going to be a warmer than normal winter.”
NOAA says Western Washington has equal chances of above, below or near normal precipitation during the three-month period. The odds slightly favor below average rainfall in Eastern Washington, according to NOAA.
Most of Washington last winter received near normal or above-average precipitation. But warm temperatures kept snowpacks low.
The Yakima River basin’s five reservoirs were full last spring, but irrigators still faced cutbacks because of low snowpacks. On Thursday, the reservoirs held less than half the normal amount of water, according to the U.S. Bureau of Reclamation. The Washington Department of Ecology says it anticipates the drought will continue into the 2016 growing season.
Bond said he doesn’t expect temperatures to be as high this winter, mostly because last year was so extraordinary.
“It’s still possible, but again, if you’re playing the odds, it’s a real long shot,” he said.
Also Thursday, the U.S. Drought Monitor upgraded portions of northwestern Washington and the Olympic Peninsula from “severe” to “moderate” drought status. The rest of Western Washington stayed in severe drought, while all of Eastern Washington remained in “extreme” drought.
The Drought Monitor is a partnership between NOAA, the U.S. Department of Agriculture and the University of Nebraska.