NWS Forecast for: Mammoth WY Issued by: National Weather Service Riverton, WY Last Update: 12:17 am MDT Sep 10, 2026

Overnight: Clear, with a low around 43. South wind around 7 mph. Thursday: Sunny, with a high near 75. Breezy, with a southwest wind 7 to 15 mph, with gusts as high as 24 mph. Thursday Night: Partly cloudy, with a low around 47. South southwest wind 7 to 14 mph, with gusts as high as 24 mph. Friday: Partly sunny, then gradually becoming sunny, with a high near 74. South wind 6 to 13 mph becoming west northwest in the afternoon. Winds could gust as high as 26 mph. Friday Night: Mostly cloudy, with a low around 44. West northwest wind 5 to 8 mph becoming light and variable after midnight. Winds could gust as high as 21 mph. Saturday: Mostly sunny, with a high near 76. Light and variable wind becoming southwest 8 to 13 mph in the afternoon. Winds could gust as high as 26 mph. Saturday Night: A slight chance of showers and thunderstorms before 9pm, then a chance of showers and thunderstorms after midnight. Mostly cloudy, with a low around 47. Southwest wind 7 to 9 mph becoming east after midnight. Winds could gust as high as 22 mph. Chance of precipitation is 50%. Sunday: A chance of showers, with thunderstorms also possible after noon. Partly sunny, with a high near 63. Breezy. Chance of precipitation is 40%. Sunday Night: A 20 percent chance of showers before midnight. Partly cloudy, with a low around 38. Monday: Mostly sunny, with a high near 62. Monday Night: Partly cloudy, with a low around 36. Tuesday: Sunny, with a high near 68. Tuesday Night: Partly cloudy, with a low around 41. Wednesday: A slight chance of showers and thunderstorms. Mostly sunny, with a high near 71.

Mammoth WY  44.98°N 110.69°W (Elev. 5745 ft)

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