JACKSON, Wyo. – Another significant storm cycle impacted the Tetons earlier this week and February as a whole ended up being the fourth straight month with above-average snowfall. Temperatures were also well below average across Teton County in February.
February 26-March 1 Storm Cycle Recap
Late February was relentless in the Tetons with snow falling on nine of the last 10 days of the month. The last storm cycle produced heavy snow over the final days of February and into the first of March with a three-day storm total of 33 inches at Jackson Hole Mountain Resort’s Rendezvous Bowl Plot.
Snow totals elsewhere included 21 inches at Jackson Hole’s mid-mountain, 17 inches at Grand Targhee, 10 inches at Snow King, 6.8 inches at Jackson Lake/Moran, and 5 inches in the Town of Jackson.
Strong winds out of the southwest resulted in rough travel conditions once again with numerous road closures. Also, on Monday afternoon, a short but intense snow squall moved through Teton County, resulting in about a 20-30 minute period of very heavy snowfall rates, strong winds and whiteout conditions.
February 2023 Recap
February was much colder than average and also snowier than average in Teton County. The month started out relatively light in terms of snowfall with infrequent snow events. However, the final 10 days of the month featured consistent heavy snow.
Jackson Hole’s Rendezvous Bowl Plot ended up with 97 inches of snow for the month of February, which is above the long-term average of 73 inches.
The Rendezvous Bowl Plot has now recorded above-average snowfall in all four months from November to February. Believe it or not, this is the first time this has ever happened since the Rendezvous Bowl Plot began recording November snowfall back in 1997 (records for snowfall from December on go back to 1974).
We have certainly had deeper winters than this one, but the month-to-month consistency of snowfall has been impressive.
The Rendezvous Bowl Plot hit 447 inches of season-to-date snowfall on February 28, which is already above average for the season and we still have another month to go. Average snowfall at this location through April 1 is 391 inches.
The Town of Jackson received 17.6 inches of snow in February, which is also above the long-term average of 13.6 inches. Almost all of Jackson’s snow accumulations occurred during the final 10 days of the month. From February 1-18, Jackson only received 0.6 inches of snow.
For the season as a whole, Jackson has now received 85 inches of snow, which is already above its entire winter season average of 75 inches.
February was also remarkably cold in the Jackson Hole Valley. In the Town of Jackson, temperatures were 7.1ºF colder than average for the month as a whole, and at the Jackson Lake weather station near Moran, temperatures were 6.1ºF colder than average.
In fact, when examining data from the Jackson COOP weather station prior to 2010 and the JKNW4 (HADS) weather station since 2010, this was “unofficially” the coldest February in the Town of Jackson since 1993!
At the Jackson Lake weather station near Moran, this February was cold but actually slightly warmer compared to 2022 and 2022.
This has also been a very cold winter as a whole. November, December, January and February were all colder than average in Jackson. The last time all four of these months were colder than average was in 2018-2019, but in general, this does not happen very often.
Given the abundance of snowfall and the consistently cold late winter temperatures, snow depth in the Town of Jackson was 27 inches on February 28. This is the deepest snowpack in town for the end of February/beginning of March since 2019 (which was a huge snow year in town).
February has been colder than average for five straight years
Normally, temperatures start to trend upward a little bit in the Jackson Hole Valley during February compared to December and January as the days get longer, but that has not been the case in recent years.
In fact, we are on a remarkable streak of five consecutive colder-than-average Februaries in Jackson, and some of these months have been well-below-average.
One possible explanation is the frequency of La Ninas in recent years, which historically correlate at least a little bit to colder late winter seasons in this part of the world. It could also be just a coincidence based on natural variations in the atmosphere.
Despite the recent string of cold Februaries, it’s doubtful this will become a long-term trend. In fact, prior to 2019, Jackson had six consecutive Februaries of above-average temperatures from 2013 to 2018.
Snowpack Update
Snowpack has increased to 107% of average in the Tetons following our most recent storm cycle. This is a healthy, but not exceptionally high snowpack given how much snow has fallen.
Snowpack percent of average is based on the amount of water contained within the snowpack. Given our cold temperatures this winter, we have had more low-density snow events than usual (even by our standards), which may partly explain why we are only slightly above average even though the amount of snow that has fallen is well above average.
Snowpack continues to run above average for the state of Wyoming as a whole.
Overall, the Western U.S. has a healthy snowpack – especially in California and Utah, which are areas that need it the most given the drought conditions in recent years.
Cold and active pattern continues into March
The first half of March is shaping up to be much colder than average, and an active storm track will also continue, resulting in frequent snow chances. Believe it or not, the average high in Jackson during March is 44ºF. But this year, highs in the 20s and 30s will be most common through the first two weeks of the month.
The next chance of snow will be on Thursday night and Friday as a storm arrives from the northwest. This storm will produce 4-8 inches of new snow in the Tetons with only light accumulations in the Jackson Hole Valley.
From Saturday afternoon through Monday, a low pressure system will set up along the West Coast and California will get slammed with storms once again. A series of disturbances associated with this system will then work its way into Western Wyoming from the southwest, providing more opportunities for snow.
Heading into the middle part of next week, confidence decreases in the forecasts based on uncertainty with the movement of the low pressure system over California. We may head into a brief drier period, but for now a slight chance of snow can still be expected on Tuesday (March 7) and Wednesday (March 8).
Even though we’re getting later in the season, consistent cold temperatures will continue to result in valley snow accumulations and winter driving conditions on roads at all elevations. Winds are uncertain, but may not be quite as strong in this pattern compared to the past two weeks.
Extended Outlook
From March 9-15, an active pattern is likely to resume with frequent snow chances along with below-average temperatures.
Alan Smith, Meteorologist
