7-Day Forecast 45.05°N 111.13°W (Text-Only)
NWS Forecast for: 18 Miles SE Big Sky MT
Issued by: National Weather Service Riverton, WY
Last Update: 12:48 pm MDT Jul 21, 2026




This Afternoon: Scattered showers and thunderstorms, mainly between 4pm and 5pm. Patchy smoke after 2pm. Partly sunny, with a high near 80. North wind 5 to 10 mph. Chance of precipitation is 30%.

Tonight: Scattered showers and thunderstorms before midnight, then isolated showers between midnight and 1am. Patchy smoke before 8pm, then patchy smoke after 9pm. Mostly cloudy, with a low around 55. Breezy, with a northwest wind 10 to 15 mph becoming light and variable in the evening. Winds could gust as high as 21 mph. Chance of precipitation is 40%.

Wednesday: Showers and thunderstorms likely before 4pm, then showers and possibly a thunderstorm between 4pm and 5pm, then showers and thunderstorms likely after 5pm. Patchy smoke before 2pm. High near 80. Calm wind becoming north around 6 mph in the afternoon. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Wednesday Night: Showers likely and possibly a thunderstorm before 7pm, then scattered showers and thunderstorms between 7pm and midnight, then scattered showers after midnight. Mostly cloudy, with a low around 54. North wind 5 to 7 mph becoming calm in the evening. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Thursday: A chance of showers, then showers likely and possibly a thunderstorm after noon. Mostly sunny, with a high near 79. Calm wind becoming west northwest around 6 mph in the afternoon. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Thursday Night: A 10 percent chance of showers and thunderstorms before midnight. Partly cloudy, with a low around 54. West wind around 5 mph becoming calm.

Friday: Sunny, with a high near 84. West southwest wind 5 to 13 mph, with gusts as high as 25 mph.

Friday Night: A 20 percent chance of showers and thunderstorms before midnight. Partly cloudy, with a low around 56.

Saturday: A 10 percent chance of showers and thunderstorms after noon. Sunny, with a high near 85.

Saturday Night: Partly cloudy, with a low around 55.

Sunday: A slight chance of showers and thunderstorms. Sunny, with a high near 85.

Sunday Night: A slight chance of showers and thunderstorms. Partly cloudy, with a low around 54.

Monday: A slight chance of showers and thunderstorms. Mostly sunny, with a high near 83.



18 Miles SE Big Sky MT
 45.05°N 111.13°W (Elev. 6916 ft)

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