Hercules, CA Weather & Growing Conditions
Overnight
56°F
Partly Cloudy
Partly cloudy, with a low around 56. Southwest wind around 8 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 56°F | Partly Cloudy | 8 mph SW | 0% |
| Tuesday | 82°F | Haze then Sunny | 7 to 13 mph SW | 0% |
| Tuesday Night | 56°F | Partly Cloudy | 7 to 12 mph SW | 0% |
| Wednesday | 79°F | Mostly Sunny | 7 to 12 mph SW | 0% |
| Wednesday Night | 56°F | Partly Cloudy | 6 to 12 mph SW | 0% |
| Thursday | 78°F | Sunny | 6 to 10 mph SW | 0% |
| Thursday Night | 57°F | Mostly Clear | 6 to 10 mph SW | 0% |
| Friday | 84°F | Sunny | 5 to 10 mph SW | 0% |
| Friday Night | 58°F | Mostly Clear | 7 to 10 mph SW | 0% |
| Saturday | 82°F | Sunny | 6 to 12 mph SW | 0% |
| Saturday Night | 59°F | Mostly Clear | 8 to 12 mph SW | 0% |
| Sunday | 79°F | Sunny | 8 to 13 mph SW | 0% |
| Sunday Night | 58°F | Mostly Clear | 14 mph SW | 0% |
| Monday | 74°F | Sunny | 10 to 14 mph SW | 0% |
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 Aug 4, 2026.