Going into the weekend, the Jackson Hole valley floor had been melting out for weeks, and sunny days with above-average temperatures had zapped a once 17-inch-deep March snowpack down to just 6 inches.
A two-day snowstorm that set a few records along the way brought the snow depth in town right back to 17 inches.
“The average snowfall in the month of March in town is only 11 inches, and we got more than that in one day,” Jackson Hole meteorologist Jim Woodmencey said.
Volunteers monitoring the National Weather Service’s Jackson Climate Station located on the National Elk Refuge logged 12 inches of new snow that fell Saturday and another 7 inches Sunday. The snowpack had compressed by Monday, which explains why the total snow depth was measuring 17 inches.
It was an exceptionally wet snowstorm, too, with just over 2 inches of water coming down in town. For perspective, the average in-town precipitation during the entire month of March is just 1.23 inches. The Jackson Climate Station received nearly all of that amount — 1.15 inches of water — during the 24-hour period between Saturday and Sunday mornings.
Woodmencey wrote on his MountainWeather.com blog that the one-day blast of precipitation is the second most ever recorded in town during the month of March in 24 hours, behind only March 3, 1995, when 1.80 inches of water fell into the station’s gauge.
The behemoth storm system, which coincided with the coronavirus-driven closure of Teton County’s three ski areas, stretched from the Pacific Ocean all the way to the Continental Divide. Resorts in the Lake Tahoe area got over 30 inches of snow — as did Jackson Hole Mountain Resort’s Rendezvous Bowl.
“It came down from Alaska to the Pacific Northwest and got stuck there,” Woodmencey said. “It just sat there and spun with a consistent southwesterly flow of moisture from the Pacific to Jackson.”
It was an unusual storm for Jackson Hole in that it was not “orthographically enhanced,” or in other words influenced heavily by the Tetons and Jackson Hole’s other mountain ranges.
“The mountains were a less significant player than usual, because of the amount of moisture that was flowing over us,” Woodmencey said. “We were going to get good precipitation, even if it was flat here.”
At the 9,580-foot Rendezvous Bowl site, 31 inches of snow, containing 2.65 inches of water, fell from Saturday to Monday morning. The 24-hour snowfall total logged Sunday morning also broke the single-day record for March 15.
The sudden flurry of snowfall propped up the spring snowpack in the Tetons, at least judging by the depth of the March snowpack in Rendezvous Bowl. The snow depth Monday morning was measuring just more than 7-1/2-feet deep, which is 130% of the long-term median for that site. Tops ever for that date in history was in 2017, when more than 12 feet was measured there March 16.
“We’re now at a top-10 snow depth for March,” Woodmencey said. “It’s not bad, considering it didn’t snow much the first half of the month.”