NWS Forecast for: Old Faithful WY Issued by: National Weather Service Riverton, WY Last Update: 6:04 pm MDT Jul 21, 2026

Flood Watch Tonight: Scattered showers and thunderstorms before midnight, then isolated showers between midnight and 3am. Patchy smoke before 11pm. Mostly cloudy, with a low around 47. East southeast wind 5 to 8 mph becoming calm after midnight. Chance of precipitation is 40%. Wednesday: Showers and thunderstorms likely, mainly between 3pm and 5pm, then showers likely and possibly a thunderstorm after 5pm. Partly sunny, with a high near 80. Calm wind becoming east northeast 5 to 8 mph in the afternoon. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible. Wednesday Night: Showers and possibly a thunderstorm before 10pm, then scattered showers and thunderstorms between 10pm and 3am, then scattered showers after 3am. Low around 46. East wind 5 to 9 mph becoming calm in the evening. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms. Thursday: A chance of showers before 9am, then a chance of showers and thunderstorms between 9am and noon, then showers likely and possibly a thunderstorm after noon. Mostly sunny, with a high near 78. Calm wind becoming west around 5 mph. Chance of precipitation is 70%. 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. Mostly clear, with a low around 46. Calm wind. Friday: Sunny, with a high near 84. Calm wind becoming west southwest 5 to 7 mph in the morning. Winds could gust as high as 22 mph. Friday Night: Partly cloudy, with a low around 48. West southwest wind around 5 mph becoming calm after midnight. Saturday: A 10 percent chance of showers and thunderstorms after noon. Sunny, with a high near 84. Saturday Night: Partly cloudy, with a low around 48. Sunday: A 20 percent chance of showers and thunderstorms after noon. Sunny, with a high near 83. Sunday Night: Mostly clear, with a low around 48. Monday: A slight chance of showers and thunderstorms. Sunny, with a high near 83. Monday Night: A slight chance of showers and thunderstorms. Mostly clear, with a low around 47. Tuesday: A slight chance of showers and thunderstorms. Sunny, with a high near 83.

Old Faithful WY  44.46°N 110.82°W (Elev. 7398 ft)

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