Grass Valley Reservoir Weather Forecast
- 51
- 68
Rain Showers
- 50
- 63
Rain Showers
- 39
- 59
Rain Showers
- 39
- 57
Mostly Sunny
- 42
- 58
Partly Sunny
- 37
- 54
Slight Chance Rain/Snow
Today 9 Oct Southern Mountains
Partly cloudy with a slight chance of Showers and Thunderstorms in the Morning, then mostly cloudy with rain Showers likely and a chance of Thunderstorms in the afternoon. Some Thunderstorms may produce heavy rainfall in the afternoon. Highs in the upper 50s. Chance of precipitation 60 percent.
Tonight 9 Oct Southern Mountains
Rain Showers likely and a slight chance of Thunderstorms in the Evening, then rain Showers and a slight chance of Thunderstorms after midnight. Some Thunderstorms may produce heavy rainfall. Lows in the mid 40s. Chance of precipitation 90 percent.
Grass Valley Reservoir Temperature Statistics
October Temperature
St George Municipal Airport (25.5 miles)
Lowest 5 October, 2025
53.1 °FAverage October
70.4 °FHighest 2 October, 2025
89.1 °F
Climate (2020–Present)
St George Municipal Airport (25.5 miles)
Average Low 2020–2025
52.3 °FAverage 2020–2025
64.2 °FAverage High 2020–2025
76.4 °F