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Threemile Reservoir, CA 7-Day Night Weather Forecast
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Threemile Reservoir, CA Weather Forecast
Threemile Reservoir, CA Weather Forecast Date: 231 AM PDT Sun Aug 09 2026
The area/counties/county of: Lassen, including the cities of: Portola, Susanville, Westwood, Sierraville, and Loyalton.or toggle through each period.
Today... Sunny. Haze and areas of smoke through the day. Highs 93 to 103. Light winds becoming west 10 to 15 mph with gusts up to 30 mph in the afternoon.
Tonight... Clear. Haze through the night. Smoke after midnight. Lows 50 to 60. West winds 10 to 15 mph with gusts up to 30 mph in the evening becoming light.
Monday... Sunny. Areas of smoke. Highs 91 to 101. Light winds becoming southwest 10 to 15 mph with gusts up to 30 mph in the afternoon.
Monday Night... Clear. Lows 50 to 60. West winds 10 to 15 mph with gusts up to 35 mph in the evening becoming light.
Tuesday... Sunny. Highs 87 to 97. Light winds becoming southwest around 10 mph in the afternoon.
Tuesday Night... Clear. Lows 50 to 60.
Wednesday... Partly cloudy with a slight chance of showers. Highs 84 to 94. Lows 47 to 57.
Wednesday Night... Partly cloudy with a slight chance of showers. Highs 84 to 94. Lows 47 to 57.
Thursday... Partly cloudy with a chance of showers and thunderstorms. Highs 81 to 91. Lows 46 to 56.
Friday... Partly cloudy with a chance of showers and thunderstorms. Highs 81 to 91. Lows 46 to 56.
Friday Night... Partly cloudy. Slight chance of showers in the evening. Lows 44 to 54.
POP = Probability of Precipitation
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