National Weather Service Forecast for: Grass Valley CA
Issued by: National Weather Service Sacramento, CA
Updated: 4:16 pm PST Dec 20, 2025
 
Overnight

Overnight: Rain. The rain could be heavy at times. Steady temperature around 51. South wind 7 to 11 mph, with gusts as high as 26 mph. Chance of precipitation is 100%. New precipitation amounts between 1 and 2 inches possible.
Heavy Rain
 Sunday

Sunday: Rain. The rain could be heavy at times. High near 53. South wind around 15 mph, with gusts as high as 33 mph. Chance of precipitation is 100%. New precipitation amounts between 3 and 4 inches possible.
Heavy Rain
 Sunday
Night
Sunday Night: Showers and possibly a thunderstorm before 1am, then rain after 1am. Some of the storms could produce heavy rainfall. Low around 46. South wind 9 to 14 mph, with gusts as high as 30 mph. Chance of precipitation is 100%. New rainfall amounts between 1 and 2 inches possible.
Heavy Rain
 Monday

Monday: Rain. High near 51. South wind around 6 mph. Chance of precipitation is 90%. New precipitation amounts between 1 and 2 inches possible.
Rain
 Monday
Night
Monday Night: Rain. Low around 45. Calm wind. Chance of precipitation is 100%.
Rain
 Tuesday

Tuesday: Rain, mainly before 1pm, then showers likely and possibly a thunderstorm after 1pm. High near 53. Chance of precipitation is 80%.
Showers
 Tuesday
Night
Tuesday Night: Rain. Low around 43. Chance of precipitation is 100%.
Rain
 Wednesday

Wednesday: Rain. Cloudy, with a high near 49.
Rain
 Wednesday
Night
Wednesday Night: Rain before 10pm, then showers and possibly a thunderstorm after 10pm. Cloudy, with a low around 42.
Showers
Lo 51 °F Hi 53 °F Lo 46 °F Hi 51 °F Lo 45 °F Hi 53 °F Lo 43 °F Hi 49 °F Lo 42 °F

Flood Watch
 

Overnight
 
 Rain. The rain could be heavy at times. Steady temperature around 51. South wind 7 to 11 mph, with gusts as high as 26 mph. Chance of precipitation is 100%. New precipitation amounts between 1 and 2 inches possible.
Sunday
 
 Rain. The rain could be heavy at times. High near 53. South wind around 15 mph, with gusts as high as 33 mph. Chance of precipitation is 100%. New precipitation amounts between 3 and 4 inches possible.
Sunday Night
 
 Showers and possibly a thunderstorm before 1am, then rain after 1am. Some of the storms could produce heavy rainfall. Low around 46. South wind 9 to 14 mph, with gusts as high as 30 mph. Chance of precipitation is 100%. New rainfall amounts between 1 and 2 inches possible.
Monday
 
 Rain. High near 51. South wind around 6 mph. Chance of precipitation is 90%. New precipitation amounts between 1 and 2 inches possible.
Monday Night
 
 Rain. Low around 45. Calm wind. Chance of precipitation is 100%.
Tuesday
 
 Rain, mainly before 1pm, then showers likely and possibly a thunderstorm after 1pm. High near 53. Chance of precipitation is 80%.
Tuesday Night
 
 Rain. Low around 43. Chance of precipitation is 100%.
Wednesday
 
 Rain. Cloudy, with a high near 49.
Wednesday Night
 
 Rain before 10pm, then showers and possibly a thunderstorm after 10pm. Cloudy, with a low around 42.
Christmas Day
 
 Rain. Cloudy, with a high near 48.
Thursday Night
 
 Rain. Cloudy, with a low around 40.
Friday
 
 Rain. Mostly cloudy, with a high near 48.
Friday Night
 
 A chance of rain. Mostly cloudy, with a low around 36.
Saturday
 
 A slight chance of rain. Mostly sunny, with a high near 51.

 

Forecast from NOAA-NWS for Grass Valley CA.