Back to back storms deliver deep snow totals to the Tetons

JACKSON, Wyo. – Two storms in five days produced a total of 20-40 inches of snow in the Tetons and 12-20 inches in the Jackson Hole Valley. Following a break in the pattern late this week, an active pattern with frequent shots of snow is expected next week.

Recent Snowfall

What a difference a few days can make! At this time last week, snowpack was near record low levels for the date, and ski areas were struggling to open up terrain due to thin conditions.

The first of two storms impacted the area on Saturday and Sunday (December 14-15) with snowfall favoring the Southern Tetons and Jackson Hole Valley.

Snow totals from this storm included 23 inches at Jackson Hole’s Rendezvous Bowl Plot, 17 inches at Jackson Hole’s Mid-Mountain Plot, 11 inches at Snow King, 9 inches at Grand Targhee, and 8 inches in the Town of Jackson.

The second storm impacted the area on Monday and Tuesday (December 16-17) with snow totals including 18 inches at Jackson Hole’s Raymer Plot, 15 inches at Jackson Hole’s Mid-Mountain Plot, 10 inches apiece at Grand Targhee and Snow King, and 5 inches in the Town of Jackson.

Total snowfall from December 14-18 includes 40 inches at Jackson Hole’s Rendezvous Bowl Plot (9,580 feet), 32 inches at Jackson Hole’s Mid-Mountain (8,180 feet), 21 inches at Snow King, and 13 inches in the Town of Jackson.

The recent snowfall has been a boon to ski areas, which are opening up new lifts and terrain by the day. The timing is good leading up to the busy holiday season, especially considering where we were a week ago.

Snowpack as measured by snow water equivalent is currently 74% of average in the Upper Snake River Basin, which is an improvement from 51% of average at this time last week.

Snow depth (the height of the snowpack) ranges from 38-50 inches in the Tetons at 9,000 feet. Snow depth values are actually right around average at Jackson Hole’s upper mountain for the date, although snow depth will likely decrease slightly over the coming days as the new snow settles.

Upcoming Weather Pattern

A storm passing north of the Tetons is producing clouds, flurries, and gusty winds over the Tetons on Wednesday.

From Thursday to Saturday, a ridge of high pressure will build over the Western U.S., resulting in dry conditions and much warmer temperatures in the mountains.

A temperature inversion will set up in the Jackson Hole Valley, however, resulting in colder temperatures compared to the mountains – especially on Friday and Saturday.

The good news for snow lovers is that an active pattern is set to return next week. Starting on Sunday and continuing beyond Christmas Day, frequent storms are expected to track across the Pacific Northwest and into the Northern Rockies with new shots of snow every one to two days or so.

The 7-day snowfall projection from the European Ensemble Model (an average of 50 simulations) is valid through Christmas morning, on December 25th.

Beyond Christmas, frequent storms are possible (if not likely) through the end of next week, and possibly through New Year’s.

Here is NOAA’s 1-2 week precipitation outlook from December 26 to January 1, which indicates a higher likelihood of above-normal precipitation.

This will be a progressive pattern with frequent storms arriving from the west/southwest – also known as a zonal flow, as opposed to amplified troughs and ridges that coincide with bigger dips in the jet stream.

This persistent westerly flow will favor mild Pacific air arriving with storms, and temperatures are likely to be warmer than normal for late December. As a result, snow quality may be a bit wetter and denser than usual, but this will vary from storm to storm.