The past week has featured very dry conditions across Jackson Hole along with a wide range of temperatures. Early last week was quite cold with a low temperature of -14 in town on the 18th and a high of only 7 on the 19th as an inversion strengthened over the Tetons, resulting in warmer temperatures in the mountains than in the valley.
A weak system late in the week helped to scour out the inversion, but brought little more than a skiff of snow to the Tetons. Much warmer air arrived to finish out the week, with a high temperature soaring to 45 in the town of Jackson on Saturday. High temperatures in the mountains were in the 30s over the weekend, leading to changing snow quality on south-facing aspects and even some loose wet avalanche activity.
With no meaningful snow over the past week, snowpack relative to average has fallen to 92% of average across the Teton and Gros Ventre Mountains.
At Jackson Hole Mountain Resort’s Rendezvous Bowl plot (9,580 ft.), the current snow depth is 45 inches, which is about 85% of the average value for the date of 52 inches.
Minor Snow Event for Christmas Eve and Christmas Day
Snow will finally return to the area on Christmas Eve (Tuesday), but this is looking like a minor event for the Tetons as the main storm track will be south of the area. Jackson Hole will be on the northern fringe of this system, as winds from the south/southwest transport moisture and snowfall into the area.
Snow will arrive between midnight and sunrise on Christmas Eve morning (Tuesday), and light snow will continue off and on throughout the day and into Christmas Eve night. Additional light snow will continue through Christmas morning (Wednesday) before tapering off in the afternoon.
Total snow amounts on Tuesday and Wednesday will range from 2-5″ in the Tetons for the most part, with maybe a few lucky areas squeezing out 6″. Temperatures will be trending colder throughout the event across the higher elevations. On Christmas Eve, mountain temperatures at 9,000 ft. will be in the low 20s with southwest winds gusting to 25-30mph. On Christmas Day, temperatures at 9,000 ft. will only be in the low teens, but winds will be lighter at least.
For the valley, highs on Tuesday will rise into the mid 30s which will limit snow accumulations. The best windows for accumulating snow in the valley will be on Tuesday morning, and again Tuesday night and Wednesday morning. Total snow accumulations will range from 1-2″ for most valley areas. Highs Wednesday will be in the upper 20s in the valley.
Minor travel impacts by Wyoming standards can be expected on Christmas Eve and Christmas Day, especially if driving over the mountain passes, but there shouldn’t be any major issues. For skiers and snowboarders, Christmas Day will offer the best chance to enjoy fresh turns.
Drying out again for the rest of the week
Unfortunately for skiers, the pattern will turn dry again from Thursday through the weekend. Temperatures will also be trending colder during this period, with inversions likely developing by the weekend. Beyond this weekend, the next chance of snow may not arrive until around New Year’s based on current long-range projections.
Alan Smith, Meteorologist
