Hercules, CA Weather & Growing Conditions
Overnight
49°F
Mostly Clear
Mostly clear, with a low around 49. East wind around 7 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 49°F | Mostly Clear | 7 mph E | 0% |
| Wednesday | 65°F | Sunny | 3 to 8 mph NNW | 2% |
| Wednesday Night | 49°F | Mostly Cloudy | 2 to 6 mph W | 2% |
| Thursday | 69°F | Mostly Sunny | 3 mph WNW | 0% |
| Thursday Night | 49°F | Mostly Clear | 2 mph W | 0% |
| Friday | 70°F | Sunny | 0 to 3 mph NNE | 0% |
| Friday Night | 49°F | Mostly Clear | 2 mph N | 0% |
| Saturday | 71°F | Sunny | 1 to 8 mph NE | 0% |
| Saturday Night | 50°F | Mostly Clear | 2 mph NW | 0% |
| Sunday | 70°F | Mostly Sunny | 1 to 5 mph NNW | 0% |
| Sunday Night | 51°F | Partly Cloudy | 2 mph SW | 0% |
| Monday | 68°F | Mostly Sunny | 1 to 5 mph WSW | 2% |
| Monday Night | 51°F | Partly Cloudy | 2 mph WSW | 2% |
| Tuesday | 69°F | Patchy Fog then Sunny | 3 mph WNW | 6% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Hercules, CA
Last spring frost
Jan 17
First fall frost
Dec 27
Growing season
346 days
Hardiness zone
9b
Explore more for Hercules, CA: full frost dates · planting calendar · California frost dates
Climate data from the nearest NOAA station, Vallejo, Ca (7.5 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.