Washington snowpack below average so far
El Nino is shaping up as expected for the Pacific Northwest this winter, resulting in warmer temperatures, drier conditions and below-average mountain snowpack in Washington, the federal government said Tuesday.
Associated Press Writer
El Nino is shaping up as expected for the Pacific Northwest this winter, resulting in warmer temperatures, drier conditions and below-average mountain snowpack in Washington, the federal government said Tuesday.
El Nino is a periodic warming of the water in the tropical Pacific Ocean accompanied by changes in air pressure and winds that can influence weather worldwide. In the Pacific Northwest, that generally means warmer and drier conditions, with above-average precipitation in the Southwest.
The warmer and drier conditions this year have resulted in mountain snowpack levels that are below average across Washington state, except on the Olympic Peninsula, said Scott Pattee, water supply specialist for the USDA's Natural Resources Conservation Service.
It's too early to know if those conditions will continue for the rest of the winter, but weather forecasters predict above-average temperatures through March, he said.
That could present challenges for water managers and water users later this summer, who rely on mountain snowpack to feed rivers and streams and fill lakes and reservoirs as it melts. Seventy to 80 percent of Washington's surface water supplies come from mountain snowmelt in the summer.
After above-average precipitation in October and heavy snowfall in November, Washington was on track for a good winter, Pattee said.
"But come December, Mother Nature just turned the faucet off," he said. "Typically, by this time, we should have a solid 50 percent of our snowpack on the ground and we're 10-15 percent behind on that right now."
Last month, the Pacific Northwest experienced the 14th-coldest December since 1895. It was also the 11th-driest December for Washington state.
The NRCS measures the depth and water content of snow at more than 100 locations around the state. That data is used to estimate how much water will flow down rivers and streams and into reservoirs as the snow melts.
Water shortages have been a regular problem in parts of the state in recent summers.
In Eastern Washington, snowpack levels ranged from 56 percent of average in the Spokane River basin to 89 percent of average in the Walla Walla area. West of the Cascades, snowpack in the central Puget Sound area registered at 72 percent of average, while the Olympic Peninsula came in at 123 percent of average.
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