Bighorn Basin Experienced Warmer, Drier December in 2021

December weather was varied in the Bighorn Basin, with several areas reporting varying amounts of precipitation and some of the warmest temperatures on record.

Throughout December, the Bighorn Basin and the entirety of Wyoming were subjected to erratic winter weather. Record highs in early December gave way to near record lows by the end –in terms of temperature and snowpack.

Wyoming’s snowpack/S.W.E. was only 66% of median amounts in mid-December. The situation had improved by the end of the month, but many basins were still much drier than usual.

According to the National Oceanic and Atmospheric Administration, November’s average temperature was about 6 degrees Fahrenheit warmer than average. Unfortunately, that trend continued into December.

The National Weather Service Office in Riverton released a climate summary for December 2021 – with warmer-than-average temperatures across the Bighorn Basin.

The N.W.S. Riverton Office published the numbers for two Bighorn Basin communities: Greybull and Worland. The average normal temperature for each community was well-above historical averages – 5.6 degrees higher in Worland and 6.2 degrees higher in Greybull.

Greybull received 0.01 inches of precipitation in December – that’s only 9% of its average amount. December 2021 was the driest in Greybull’s recorded history, back to 1998.

Meanwhile – just down Highway 20 – Worland had more than enough precipitation. 0.19 inches of precipitation fell on Worland in December. It’s not much, but it is 106% of the city’s average amount.

Many western Wyoming communities got varying precipitation, but it was warmer everywhere.

Across western Wyoming, the wettest December community was Buffalo. Overall, Buffalo received 0.40 inches of precipitation – 235% of average amounts and the second wettest December in the city since 1998 (when record-keeping started.)

Riverton, however, was much drier. Both the community and the airport reported just over a quarter of their average precipitation (26% and 27%, respectively.)

But everywhere, December was warmer. Much warmer.

Lander’s average December temperature was 9.9 degrees warmer in 2021. Riverton was even warmer, with average temperatures 12.8 degrees warmer.

For the nine communities reported by the N.W.S., December 2021 was – on average – 7.07 degrees warmer than average.

The weather of December 2021 cannot accurately gauge how warm and wet the ongoing winter will be. However, if these trends continue, western Wyoming could be reckoning with a much drier and dangerous spring and summer in 2022.