45°46'N / 111°11'W / Altitude 1359 m / 14:02 2026/04/21, America/Denver (UTC-6)
From: 2026/04/20, 23:33
To: 2026/04/21, 18:15
* WHAT...Heavy snow possible. Total snow accumulations between 4 and 10 inches, with isolated higher amounts possible. Winds could gust as high as 50 mph. * WHERE...Big Belt, Bridger and Castle Mountains, Little Belt and Highwood Mountains, and Gallatin and Madison County Mountains and Centennial Mountains. * WHEN...From Wednesday evening through Thursday afternoon. * IMPACTS...Tire chains may be required for some vehicles if traveling through mountain passes. Strong winds could cause tree or power line damage.
Gallatin
Remember, a Winter Storm Watch means that there is at least a 50%
chance of impactful winter weather conditions during the watch
period.
To see a graphical representation of the degree of stress on young
livestock please visit our webpage and select Local Programs then
Cold Air Advisory for Newborn Livestock.
NWS Great Falls MT
2026/04/20, 23:33
From: 2026/04/21, 12:09
To: 2026/04/22, 07:00
* WHAT...Snow expected. Total snow accumulations between 6 and 12 inches with the highest amounts across southwestern portions of the Park. Winds gusting as high as 40 mph. * WHERE...Yellowstone National Park. * WHEN...From noon Wednesday to 11 PM MDT Thursday. * IMPACTS...Travel could be very difficult. * ADDITIONAL DETAILS...Total snow amounts up to 3 inches at Mammoth.
GallatinSlow down and use caution while traveling.
For graphical depictions of the snowfall forecast, including the
official NWS forecast, high end amounts, and low end amounts, visit
https://weather.gov/riw/winter.
For current road conditions across Yellowstone National Park, visit
https://nps.gov/yellowstone.NWS Riverton WY2026/04/21, 12:09