From Lander to Sheridan, Laramie to Evanston and almost everywhere in between, the 2025-26 winter officially goes down as the warmest winter since recordkeeping began in the 19th century.
The December-through-February period — known as the meteorological winter — set new high marks for average low temperature, average temperature overall and average high temperatures. Record heat across the season was recorded where climate stations were relatively new. And thermometers also climbed higher than ever before, where daily highs and lows have been recorded for 135 years, which is the case in Lander.
Lander’s three-month average maximum temperature was 47.7 degrees; its average overall was 34.6 degrees and the average minimum was 21.6 degrees. Each set the new all-time high mark, surpassing the historically warm winter of 1933-’34, according to National Weather Service Meteorologist Adam Dziewaltowski.
“That was one of the worst years for the Dust Bowl,” Dziewaltowski told WyoFile. “So it’s not good company.”
All other climate stations monitored by the National Weather Service’s Riverton Office set their all-time warmest winter records, including in Big Piney, Buffalo, Casper, Cody, Greybull, Jackson, Lake Yellowstone, Riverton and Rock Springs. The office posted about it on Facebook, sharing the official numbers as well as the departures from average.
Several other National Weather Service offices monitor other portions of Wyoming. Querying data from those in Cheyenne, Billings, Salt Lake City and Rapid City, WyoFile learned of only one climate station that did not register its warmest winter on record. That was in Newcastle, which had its second-warmest winter on record.
“Obviously, there’s going to be some place or some elevation where it’s not going to be the warmest winter,” Wyoming State Climatologist Tony Bergantino said. “But I think you can say, generally speaking, around the state, it’s been the warmest.”
Bergantino is awaiting a batch of Wyoming climate station data to go through quality control. By around March 7, he said, there should be more finalized figures to describe the anomalous winter.
Lower-elevation areas in particular were unseasonably warm. Most in Wyoming were more than 10 degrees above average. Mountainous areas, especially in the northwest, weren’t as divergently hot — and the high-elevation snowpack in a handful of river basins is even near average.
But down low, it was a completely different story. Lander, for example, sits in the Wind River Basin, where the snowpack on Monday was 103% of the long-term median. But at the climate station, located at the 5,589-foot-elevation Hunt Field airport, just 8.2 inches of snowfall was recorded over the three winter months — the least ever, and just 16% of the average in-town snowfall of 52.9 inches, Dziewaltowski said.
Sometimes thermometers toppled previous records by significant margins.
Over the 90 days of winter in Sheridan, temperatures breached 60 degrees on 20 different days and 50 degrees on 44 days.
“So practically half of the meteorological winter had highs over 50 degrees Fahrenheit,” said William McKeown-Robbie, a Weather Service meteorologist out of the Billings office.
Lander also had its share of especially unseasonably warm days. December hit a new monthly record high temperature. And there were two days in December, three days in January and one day in February that cracked the top 10 all-time highs for the month.
Christmas Eve in Lander reached 65 degrees, beating the previous all-time high by a whopping 10 degrees in a dataset that traces back to 1891.
“Very strong” high-pressure systems consistently parked south of Wyoming near the Four Corners region partly explains the record-setting season that’s now passed by.
“That kept anything coming down from Canada and the Arctic east of us,” Dziewaltowski said.