JACKSON, Wyo. — A strong storm arriving from the northwest will bring a round of snow to the higher elevations on Monday and Tuesday, but the greatest impact will be the high winds expected.
The National Weather Service in Riverton has issued a High Wind Warning for Teton County from 3 p.m. Monday until 3 p.m. Tuesday. In fact, the majority of Wyoming, Idaho and Montana are all under a High Wind Warning for the next couple of days, so this will be a widespread event.
Winds will begin to pick up out of the southwest on Monday afternoon with gusts to 40-50 mph possible in the Jackson Hole Valley by late in the day. The strongest winds are then expected on Monday night with gusts as high as 65 mph possible in the valley. The higher elevations of the Tetons could see gusts exceeding 80 mph.
Winds will continue to be strong on Tuesday with gusts to 40-50 mph possible in the valley before eventually subsiding on Tuesday evening.
Travel is going to be challenging, especially over Teton Pass and other mountain passes, from Monday afternoon through Tuesday afternoon. In fact, road closures are a strong possibility over Teton Pass on Monday night due to the combination of high winds and moderate to heavy snow. Even in the valleys, high winds and blowing dust may result in difficult driving conditions.
A strong pressure gradient (difference in pressure over a horizontal distance) associated with a cold front and a large difference in temperatures ahead of and behind the front, along with a powerful jet stream maximum moving into NW Wyoming, will be major contributing factors to this wind event.
Snowfall will begin over the Tetons by late Monday morning and will continue into Monday evening, then will become less widespread/more scattered late Monday night when wind gusts are at their strongest. Additional snow showers will re-develop during the day on Tuesday.
The valley will see a rain/snow mix during this event and accumulations on Monday-Monday night are unlikely. Precipitation will be all-snow for the valley on Tuesday but any accumulations will be minor if anything. Temperatures will also be much colder on Tuesday behind a cold front that moves through late Monday night.
The Tetons above 8,000 feet will pick up 4-8 inches of new snow on Monday-Monday night and an additional 1-3 inches on Tuesday. Areas above 8,000 feet are under a Winter Weather Advisory from noon on Monday until noon on Tuesday.
Stay tuned for a weekly weather report with more details to be issued late morning or early afternoon on Monday.
Alan Smith, Meteorologist
