JACKSON, Wyo. — A cold front will move through on Wednesday morning with a quick round of snow expected in the Tetons while the valley will see little to no accumulation. A strong storm system will impact the area on Friday night and Saturday with heavy snow possible. This will kick off an active pattern with additional storms likely through next week.
October 25-31 Recap
Last week started out active with snow falling on Tuesday (10/25) and Wednesday (10/26) along with below-average temperatures. Over this two-day period, the Tetons picked up about 6 inches of snow above 9,000 feet, with 4 inches at 8,000 feet and 1-3 inches on the valley floor.
A dry pattern then took hold from Thursday (10/27) through Monday (10/31) with gradually moderating temperatures. Highs topped 50 degrees in the valley over each of the previous four days, but limited daylight hours supported cold overnight lows well into the teens.
High temperatures last week ranged from 35ºF on October 26 to 55ºF on October 31, and low temperatures ranged from 13ºF on October 28 to 28ºF on October 25.
Forecast for Tuesday (11/1) to Monday (11/7)
The latest mild spell will soon be coming to an end with a colder and more active pattern ahead. The first storm this week will not be taking a favorable path to produce significant snowfall in the Tetons, but it will bring noticeable changes to the weather.
Ahead of the storm on Tuesday, highs will warm up into the upper 50s in the valley and strong south/southwest winds will also develop in the afternoon.
Early Wednesday morning, a cold front will arrive resulting in a short but heavy burst of snowfall in the Tetons just before sunrise and into morning commute. Teton Pass commuters should be prepared for poor driving conditions on Wednesday morning as roads will quickly ice up and strong winds could lead to reduced visibility.
Most of the snow will fall early in the day with additional scattered snow showers possible in the afternoon. The Tetons will pick up 2-4 inches of new snow. In the valley, precipitation could briefly start as rain or a rain/snow mix early Wednesday before turning to all-snow. However, little to no accumulation is expected in the valley as temperatures will remain above freezing.
Cold and slightly unsettled conditions will prevail on Thursday with highs in the mid 30s. Occasional flurries will be possible on Thursday, but it won’t amount to much if anything.
Attention then turns to the weekend with a strong storm expected to impact the area on Friday night and Saturday. This storm will involve a powerful jet stream along with a plume of significant Pacific moisture – a pattern known as an “atmospheric river” or in more informal terms, a “Pineapple Express.”
Snow could begin as early as Friday afternoon, then will become heavy on Friday night and Saturday with significant accumulations expected in the Tetons. The valley will see accumulating snow to start, but warmer air will arrive on Saturday, which will result in daytime melting down low and rain could potentially mix in with snow as well.
Snow chances will persist into Saturday night with mixed precipitation likely changing back over to snow in the valley. Another storm is then possible on Sunday and/or Monday with more snow for the Tetons, but confidence is low in terms of timing, temperatures and valley snow potential.
An active pattern is likely next week with new storms expected on a frequent basis through mid to late next week. The pattern looks very favorable for building up an early-season snowpack with ski resorts only weeks away from opening.
Temperatures will also be on the colder side of average next week with highs generally expected to be in the 30s in the valley.
Alan Smith, Meteorologist
Town of Jackson Climatology for November 1-7:
Average High: 47
Average Low: 19
Record High: 67 (November 3, 1921)
Record Low: -14 (November 4, 1935)
Precipitation Since Oct 1st: 0.97″ (69% of average)
Town Snowfall Since Oct 1st: 4.7″ (estimated)
Rendezvous Bowl Snowfall Since Oct 1st: 29″
Rendezvous Bowl Snow Depth: 10″