National Weather Service Forecast for: Hercules CA
Issued by: National Weather Service San Francisco Bay Area/Monterey, CA
Updated: 11:55 pm PST Dec 22, 2025
 
Overnight

Overnight: A 40 percent chance of rain. Areas of fog. Otherwise, cloudy, with a low around 53. Southeast wind 3 to 5 mph.
Chance Rain
and Areas Fog

 Tuesday

Tuesday: Rain likely, mainly between 4pm and 5pm. Patchy fog before 10am. Otherwise, cloudy, with a high near 58. South wind 6 to 16 mph, with gusts as high as 30 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.
Rain Likely
and Patchy
Fog
 Tuesday
Night
Tuesday Night: Rain. Low around 52. Breezy, with a south wind 18 to 28 mph, with gusts as high as 47 mph. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.
Rain and
Breezy

 Wednesday

Wednesday: Rain, mainly before 4pm, then showers and possibly a thunderstorm after 4pm. Some of the storms could be severe. Patchy fog between 9am and 10am. High near 57. Southwest wind 5 to 10 mph becoming south southeast in the afternoon. Winds could gust as high as 21 mph. Chance of precipitation is 80%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Rain and
Patchy Fog
then Severe
T-Storms
 Wednesday
Night
Wednesday Night: Showers and possibly a thunderstorm before 7pm, then rain after 7pm. Some of the storms could be severe. Low around 51. South southeast wind 14 to 20 mph, with gusts as high as 37 mph. Chance of precipitation is 100%. New precipitation amounts between a half and three quarters of an inch possible.
Severe
T-Storms
then Rain
 Christmas
Day
Christmas Day: Showers and possibly a thunderstorm. High near 53. Breezy. Chance of precipitation is 100%. New rainfall amounts between a half and three quarters of an inch possible.
Showers and
Breezy

 Thursday
Night
Thursday Night: Showers and possibly a thunderstorm. Low around 47. Chance of precipitation is 100%.
Showers

 Friday

Friday: Rain. Cloudy, with a high near 51.
Rain

 Friday
Night
Friday Night: Rain likely, mainly before 10pm. Patchy fog after 4am. Otherwise, mostly cloudy, with a low around 44.
Rain Likely
and Patchy
Fog
Lo 53 °F Hi 58 °F Lo 52 °F Hi 57 °F Lo 51 °F Hi 53 °F Lo 47 °F Hi 51 °F Lo 44 °F

Flood Watch
Wind Advisory
 

Overnight
 
 A 40 percent chance of rain. Areas of fog. Otherwise, cloudy, with a low around 53. Southeast wind 3 to 5 mph.
Tuesday
 
 Rain likely, mainly between 4pm and 5pm. Patchy fog before 10am. Otherwise, cloudy, with a high near 58. South wind 6 to 16 mph, with gusts as high as 30 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.
Tuesday Night
 
 Rain. Low around 52. Breezy, with a south wind 18 to 28 mph, with gusts as high as 47 mph. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.
Wednesday
 
 Rain, mainly before 4pm, then showers and possibly a thunderstorm after 4pm. Some of the storms could be severe. Patchy fog between 9am and 10am. High near 57. Southwest wind 5 to 10 mph becoming south southeast in the afternoon. Winds could gust as high as 21 mph. Chance of precipitation is 80%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Wednesday Night
 
 Showers and possibly a thunderstorm before 7pm, then rain after 7pm. Some of the storms could be severe. Low around 51. South southeast wind 14 to 20 mph, with gusts as high as 37 mph. Chance of precipitation is 100%. New precipitation amounts between a half and three quarters of an inch possible.
Christmas Day
 
 Showers and possibly a thunderstorm. High near 53. Breezy. Chance of precipitation is 100%. New rainfall amounts between a half and three quarters of an inch possible.
Thursday Night
 
 Showers and possibly a thunderstorm. Low around 47. Chance of precipitation is 100%.
Friday
 
 Rain. Cloudy, with a high near 51.
Friday Night
 
 Rain likely, mainly before 10pm. Patchy fog after 4am. Otherwise, mostly cloudy, with a low around 44.
Saturday
 
 A slight chance of rain before 10am. Patchy fog before 10am. Otherwise, mostly sunny, with a high near 52.
Saturday Night
 
 Mostly clear, with a low around 40.
Sunday
 
 Sunny, with a high near 50.
Sunday Night
 
 Mostly clear, with a low around 40.
Monday
 
 Mostly sunny, with a high near 51.

 

Forecast from NOAA-NWS for Hercules CA.