Snow totals in the high mountains all around Jackson Hole continue to grow and register well above average despite a decidedly light winter at the lower elevations.
It’s an unusual situation, and one that explains why the National Elk Refuge has so far been able to put off feeding elk later than they have in decades, and also why the Town Downhill ski race is being moved from Snow King Mountain to higher-elevation Jackson Hole Mountain Resort.
Coming on the heels of winter 2016/17, which was of several-times-a-century severity, the high-elevation snowpack has Bureau of Reclamation officials eyeing a flush year, with a lot of water flowing through Jackson Lake and Palisades Reservoir.
“The Snake River on the Idaho side and the Wyoming side are both at 118 percent of normal for the snowpack,” said Corey Loveland, who manages water operations for Upper Snake basin.
“We’re in a situation where I think we’re probably past a dry year, and it could potentially turn wet,” he said. “If that’s the case we’ll be dumping a lot of water, because we’re full in all our reservoirs.”
Enough snowpack has built up in places like the Teton Wilderness’ Two Ocean Plateau, where it’s 148 percent of the average for early March, that the National Oceanic and Atmospheric Administration is forecasting a “moderate through high” chance of flooding in the downstream portions of Pacific Creek.
Hydrological experts also forecast a moderate risk of flooding in the lowest reaches of the Buffalo Fork and Gros Ventre rivers.
The relatively snowiest portions of Wyoming are in the Greater Yellowstone Ecosystem, but across the Continental Divide: Both the Yellowstone and Shoshone river drainage are registering snowpacks that are 165 percent of average, in terms of water weight.
The snowpack is heavier than normal in all corners of the Snake River watershed in Wyoming at the highest elevations. The Gunsight Pass station at 9,820 feet in the Leidy Highlands is at 118 percent of normal, and Togwotee Pass, at 9,580 feet, is registering 140 percent of its average weight.
Snow conditions along the highest slopes at Grand Targhee and Jackson Hole Mountain Resort continue to beat the average, with skiers enjoying a 100-plus-inch depth at the peak of both Fred’s and Rendezvous mountains.
Lower down, the snowpack’s relatively slimmer. At Grassy Lake, 7,265 in elevation, the snowpack hits the average right on the nose, and it’s barely above average, 102 percent, at the Teton Range’s 8,200-foot Phillips Bench station.
Although the valley floor holds remnants of late-February snowstorms, slopes of buttes around town are relatively open and the snow depth is minimal.
National Weather Service-Riverton meteorologist Brett McDonald said that warm nights and winter rain could partly explain the lack of snow down low while there’s an abundance up high. In January and February the average nighttime low temperature in Jackson was right around 8 degrees warmer than usual, he said.
“Those warmer overnight temperatures, with typical daytime temperatures that get up to freezing and the 30s, would cause melting to occur more easily,” McDonald said.
While on the phone with the Jackson Hole Daily on Friday late morning, McDonald went to check the data for the Jackson Hole Airport. The weather station told him it was 36 degrees and raining.