JACKSON, Wyo. — The winter of 2021-2022 has been disappointing for snowfall in the Tetons. In terms of April 1 snowpack (the amount of snow on the ground), this year is the lowest for the Teton Range since 2006-2007.
April 1 is the standard date used across the Western U.S. to evaluate snowpack relative to historical averages just prior to the spring runoff season.
The current snow depth at Jackson Hole Mountain Resort’s Rendezvous Bowl Plot (elevation 9,580 feet) is 71 inches, which is only 68% of the average value of 104 inches for April 1. The last time the April 1 snow depth was lighter was in 2007 (65 inches).
For the Teton Range as a whole (based on data from multiple locations), snowpack as of April 1 ranges from 65-70% of average.
Below is a graph showing April 1 snow depth at the Rendezvous Bowl Plot over the past 30 years, for historical context.
The snow telemetry (SNOTEL) station at Grand Targhee measures both snow depth and snow water equivalent (the amount of water contained in the snowpack). The Grand Targhee Snotel has been in operation since 2007, and this year was tied with 2015 for the lowest April 1 snow depth (84 inches).
However, in terms of snow water equivalent, this has been the lightest snowpack for Grand Targhee since records began in 2007.
This winter got off to a promising start during the second half of December and the first week of January. But since early January, the pattern has been abnormally dry with only infrequent storms.
The Rendezvous Bowl Plot received an impressive 111 inches of snow in December, which was above average. However, snowfall was well below average in January (58 inches), February (26 inches), and March (46 inches).
Since October 1, the Rendezvous Bowl Plot has received 320 inches of snow, which is well below the seasonal average (through April 1) of 394 inches.
Last spring, we entered a drought in Teton County and across Western Wyoming, and unfortunately, this winter’s low snowpack has only worsened the drought status. As of March 29, Teton County and all of Western and Northern Wyoming are facing a severe to extreme drought.
Widespread drought conditions are present across most of the Western U.S. as well, with the only exceptions being the Washington and Northern Oregon Cascades, as well as the Idaho Panhandle and Northwest Montana.
The next few months will be critical as far as moisture, drought conditions and summer fire danger are concerned. The last time we had a dry winter in 2015, abundant late spring and summer rainfall (relative to average) helped us avoid a bad fire and smoke season, so not all hope is lost yet for this year.
The first half of April is looking fairly cool and active, so we will have opportunities to pick up some needed moisture over the coming weeks. In fact, a significant late-season winter storm is likely early next week (stay tuned for Monday’s weather report, which will cover this storm).
We are currently in a La Nina phase, which is expected to gradually weaken heading into the summer months. Historically, La Nina winters correlate to abundant snowfall in the Tetons, but that clearly did not happen this winter.
There is minimal correlation between La Nina years and spring (April-June) precipitation in the Tetons, so this spring could go either way.
It’s unlikely we will see enough precipitation to make up much ground on our drought conditions after such a dry winter along with a pre-existing drought.
Winter snowpack does play a role in summer fire danger, but spring and early summer weather patterns (precipitation and temperatures) actually have a greater influence on summer fire danger compared to winter snowpack.
For example, a deep winter followed by a warm/dry spring can lead to a bad fire season, whereas the opposite (dry winters followed by cool/wet springs) is also true.
Of course, if we were to follow our dry winter with a warm and dry spring, then fire danger would certainly become elevated this summer.
Alan Smith, Meteorologist
