Weather WorldGem Lake, CA 7-Day Night Weather Forecast
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Gem Lake, CA Weather Forecast
Gem Lake, CA Weather Forecast Date: 231 PM PDT Sun Sep 20 2026
The area/counties/county of: Lassen, including the cities of: Portola, Susanville, Westwood, Sierraville, and Loyalton.or toggle through each period.
Tonight... Mostly cloudy. Lows 44 to 54. Light winds.
Monday... Mostly cloudy in the morning then becoming partly cloudy. Highs 76 to 86. Light winds becoming east around 10 mph in the afternoon.
Monday Night... Mostly cloudy in the evening then clearing. Lows 42 to 52. West winds 10 to 15 mph.
Tuesday... Sunny. Highs 77 to 87. Light winds.
Tuesday Night... Clear. Lows 40 to 50. West winds around 10 mph in the evening becoming light.
Wednesday... Sunny. Highs 79 to 89.
Wednesday Night... Partly cloudy. Lows 42 to 52.
Thursday... Partly cloudy. Highs 77 to 87. Lows 41 to 51.
Thursday Night... Partly cloudy. Highs 77 to 87. Lows 41 to 51.
Friday... Partly cloudy. Highs 70 to 80. Lows 35 to 45.
Saturday... Partly cloudy. Highs 70 to 80. Lows 35 to 45.
POP = Probability of Precipitation
Gem Lake Radar Loop
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