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Mammoth, WY Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Mammoth, a community in Park County, Wyoming.

Tonight
49°F
Isolated Showers And Thunderstorms
Isolated showers and thunderstorms before 1am, then scattered showers and thunderstorms between 1am and 4am, then isolated showers and thunderstorms between 4am and 5am, then scattered showers and thunderstorms. Mostly cloudy. Low around 49, with temperatures rising to around 52 overnight. Southwest wind around 3 mph. Chance of precipitation is 40%. New rainfall amounts between a tenth and quarter of an inch possible.

7-day forecast for Mammoth

WhenTempForecastWindPrecip
Tonight 49°F Isolated Showers And Thunderstorms 3 mph SW 35%
Saturday 57°F Scattered Showers And Thunderstorms 1 to 5 mph WNW 56%
Saturday Night 46°F Chance Showers And Thunderstorms 6 mph NW 54%
Sunday 64°F Slight Chance Rain Showers then Slight Chance Showers And Thunderstorms 1 to 5 mph W 18%
Sunday Night 44°F Partly Cloudy 5 mph SW 3%
Monday 71°F Mostly Sunny 3 mph SSW 1%
Monday Night 46°F Mostly Clear 5 mph SSW 1%
Tuesday 73°F Mostly Sunny 5 mph S 1%
Tuesday Night 47°F Partly Cloudy 5 mph SSW 7%
Wednesday 73°F Sunny 6 mph SSW 7%
Wednesday Night 47°F Mostly Clear 7 mph SSW 4%
Thursday 75°F Sunny 5 mph S 3%
Thursday Night 48°F Partly Cloudy 3 to 7 mph S 1%
Friday 75°F Mostly Sunny 6 mph S 2%

Forecast source: National Weather Service (api.weather.gov) for Mammoth (44.973, -110.693). Updated through the day.

Growing snapshot for Mammoth

Last spring frost
May 21
First fall frost
Sep 27
Growing season
128 days
Hardiness zone
4b

More local growing data for Mammoth: nearby ZIP 59030 weather · frost dates · planting calendar · Wyoming frost dates

Climate data from the nearest NOAA station, Gardiner, Mt (6.5 mi from Mammoth). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.