National Weather Service Forecast for: Saint Helena CA
Issued by: National Weather Service San Francisco Bay Area/Monterey, CA
Updated: 1:25 am PST Dec 22, 2025
 
Today

Today: Rain. Widespread fog, mainly after 4pm. High near 56. Calm wind. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch possible.
Rain and Fog
 Tonight

Tonight: Rain. Widespread fog. Low around 50. Calm wind. Chance of precipitation is 100%. New precipitation amounts between a quarter and half of an inch possible.
Rain and Fog
 Tuesday

Tuesday: Rain. Areas of fog. High near 55. South southeast wind around 7 mph, with gusts as high as 22 mph. Chance of precipitation is 80%. New precipitation amounts between a half and three quarters of an inch possible.
Rain and
Areas Fog
 Tuesday
Night
Tuesday Night: Rain, mainly before 4am. The rain could be heavy at times. Low around 45. South wind 11 to 14 mph, with gusts as high as 38 mph. Chance of precipitation is 100%. New precipitation amounts between 1 and 2 inches possible.
Heavy Rain
 Wednesday

Wednesday: Rain, mainly after 10am. Areas of fog. High near 54. South southeast wind 3 to 5 mph. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.
Rain and
Areas Fog
 Wednesday
Night
Wednesday Night: Showers and possibly a thunderstorm. Patchy fog before 10pm. Low around 47. Chance of precipitation is 100%. New rainfall amounts between 1 and 2 inches possible.
Showers and
Patchy Fog
 Christmas
Day
Christmas Day: Showers and possibly a thunderstorm before 10am, then rain after 10am. Patchy fog after 4pm. High near 50. Chance of precipitation is 100%.
Showers and
Patchy Fog
 Thursday
Night
Thursday Night: Rain. Patchy fog. Otherwise, cloudy, with a low around 43.
Rain and
Patchy Fog
 Friday

Friday: Rain likely, mainly before 4pm. Areas of fog before 4pm, then patchy fog after 5pm. Otherwise, mostly cloudy, with a high near 51.
Rain Likely
and Areas Fog
Hi 56 °F Lo 50 °F Hi 55 °F Lo 45 °F Hi 54 °F Lo 47 °F Hi 50 °F Lo 43 °F Hi 51 °F

Flood Watch
High Wind Watch
 

Today
 
 Rain. Widespread fog, mainly after 4pm. High near 56. Calm wind. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch possible.
Tonight
 
 Rain. Widespread fog. Low around 50. Calm wind. Chance of precipitation is 100%. New precipitation amounts between a quarter and half of an inch possible.
Tuesday
 
 Rain. Areas of fog. High near 55. South southeast wind around 7 mph, with gusts as high as 22 mph. Chance of precipitation is 80%. New precipitation amounts between a half and three quarters of an inch possible.
Tuesday Night
 
 Rain, mainly before 4am. The rain could be heavy at times. Low around 45. South wind 11 to 14 mph, with gusts as high as 38 mph. Chance of precipitation is 100%. New precipitation amounts between 1 and 2 inches possible.
Wednesday
 
 Rain, mainly after 10am. Areas of fog. High near 54. South southeast wind 3 to 5 mph. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.
Wednesday Night
 
 Showers and possibly a thunderstorm. Patchy fog before 10pm. Low around 47. Chance of precipitation is 100%. New rainfall amounts between 1 and 2 inches possible.
Christmas Day
 
 Showers and possibly a thunderstorm before 10am, then rain after 10am. Patchy fog after 4pm. High near 50. Chance of precipitation is 100%.
Thursday Night
 
 Rain. Patchy fog. Otherwise, cloudy, with a low around 43.
Friday
 
 Rain likely, mainly before 4pm. Areas of fog before 4pm, then patchy fog after 5pm. Otherwise, mostly cloudy, with a high near 51.
Friday Night
 
 A chance of rain, mainly before 10pm. Widespread fog, mainly after 10pm. Otherwise, partly cloudy, with a low around 37.
Saturday
 
 A slight chance of rain. Widespread fog. Otherwise, mostly sunny, with a high near 53.
Saturday Night
 
 Patchy fog. Patchy frost. Otherwise, mostly cloudy, with a low around 36.
Sunday
 
 Areas of fog. Patchy frost. Otherwise, partly sunny, with a high near 54.

 

Forecast from NOAA-NWS for Saint Helena CA.