As Sun Valley enters the new year with the sparsest early-January snow cover since 1998, a ridge of high pressure off the West Coast that is forcing storms to the north of central Idaho shows no sign of breaking down, the National Weather Service says.
Sun Valley Resort is reporting a season total of 38 inches of snow, with a 19-inch snowpack at the top of the mountain and a 15-inch snowpack at the base. But despite the meager snow, skiers and boarders on Bald and Dollar mountains have been reporting remarkably decent conditions created by the resort’s snowmaking and grooming crews.
The Natural Resources Conservation Service’s Snotel site at Chocolate Gulch north of Ketchum, at 6,440 feet elevation, shows only 6 inches of snow, and the Galena Summit site at 8,780 feet shows 26 inches.
Since 1961, the NRCS has also kept a record of the snow-water content at seven sites in the upper Wood River Valley, by measuring the weight of the snow and translating it into inches of water. The data are recorded on the first day of each month of the winter. According to the agency’s records, this is the eighth driest early January in the Wood River Valley since 1961.
The driest year was 1977, when only 4 inches of water content was recorded on Jan. 1. This year, the agency measured 33 inches. The wettest year on record was 1997, with a total of 160.7 inches. Average since 1961 is 57.6 inches.
Sun Valley is not alone in its snow woes. Ski areas in the Sierra Nevada and Cascade mountains report unusually sparse snow. Squaw Valley in California has only 18 inches of snow at its base area and 20 inches 2,000 feet up the mountain. Heavenly Valley near Lake Tahoe has only 181 acres of terrain open out of a total of 4,800 acres. Mt. Bachelor in Oregon reports a 26-inch snowpack at its base and 41 inches at mid mountain. Crystal Mountain in Washington has only 12 inches of snow at its base and 49 inches at the summit.
Dean Hazen, science officer with the National Weather Service in Pocatello, said the current drought is being caused by a persistent high-pressure ridge along the West Coast that is forcing storms to the north. He said those storms are dropping snow in northern Idaho and northwestern Montana, then moving southeast into Wyoming and northern Colorado.
Jackson Hole Resort in Wyoming reports that it has received 171 inches of snow so far this season, and Steamboat in northern Colorado reports 174 inches.
“The best flow for us is a southwest flow,” he said. “We’re just not seeing a lot of southwest flow developing.”
Hazen said the snow that has fallen in the Wood River Valley this winter has been the result of uplift created by mountains rather than by moisture-laden air masses.
The high-pressure ridge has created record dry conditions in California. San Francisco, which started recording rainfall 164 years ago, had only 5.59 inches of rain in 2013, far below the city’s previous low record of 9 inches in 1917, according to National Weather Service data.
Though some snow showers are forecast this week, Hazen said there’s no indication of a permanent breakup of the high-pressure ridge occurring in the near future.
He said the long-term outlook for the winter is neutral, meaning chances are about equal for below-normal, normal or above-normal precipitation.
“We have to remember that we have another two and a half to three months to accumulate snow,” he said. “There’s still a chance that we’ll end up being normal or near normal.”