Weather WorldGrass Lake, CA 7-Day Night Weather Forecast
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Grass Lake, CA Weather Forecast
Grass Lake, CA Weather Forecast Date: 232 PM PDT Wed Sep 09 2026
The area/counties/county of: Lassen, including the cities of: Portola, Susanville, Westwood, Sierraville, and Loyalton.or toggle through each period.
Tonight... Clear in the evening then becoming partly cloudy. Lows 49 to 59. Light winds.
Thursday... Partly cloudy. Highs 83 to 93. Light winds becoming west 10 to 15 mph with gusts up to 30 mph in the afternoon.
Thursday Night... Clear. Lows 46 to 56. West winds 10 to 15 mph with gusts up to 30 mph in the evening becoming light.
Friday... Sunny. Highs 80 to 90. Light winds becoming west 10 to 15 mph with gusts up to 30 mph in the afternoon.
Friday Night... Clear. Lows 43 to 53. Southwest winds 10 to 15 mph. Gusts up to 30 mph in the evening.
Saturday... Breezy, sunny. Highs 69 to 79.
Saturday Night... Breezy, clear. Lows 31 to 41.
Sunday... Clear. Highs 61 to 71. Lows 35 to 45.
Sunday Night... Clear. Highs 61 to 71. Lows 35 to 45.
Monday... Clear. Highs 67 to 77. Lows 38 to 48.
Tuesday... Clear. Highs 67 to 77. Lows 38 to 48.
POP = Probability of Precipitation
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