San Miguel, CA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for San Miguel, a community in Contra Costa County, California.
Overnight
47°F
Mostly Clear
Mostly clear, with a low around 47. North wind around 3 mph.
7-day forecast for San Miguel
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 47°F | Mostly Clear | 3 mph N | 0% |
| Wednesday | 68°F | Sunny | 2 to 7 mph NNW | 2% |
| Wednesday Night | 46°F | Mostly Cloudy then Patchy Fog | 2 mph SW | 2% |
| Thursday | 73°F | Patchy Fog then Mostly Sunny | 1 to 5 mph NW | 0% |
| Thursday Night | 47°F | Clear | 2 mph WNW | 0% |
| Friday | 74°F | Sunny | 0 to 5 mph N | 0% |
| Friday Night | 48°F | Mostly Clear | 2 mph N | 0% |
| Saturday | 76°F | Sunny | 1 to 5 mph NE | 0% |
| Saturday Night | 48°F | Mostly Clear | 2 mph NW | 0% |
| Sunday | 74°F | Sunny | 1 to 5 mph NNW | 0% |
| Sunday Night | 49°F | Partly Cloudy | 2 mph WNW | 0% |
| Monday | 71°F | Mostly Sunny | 1 to 5 mph SW | 2% |
| Monday Night | 48°F | Partly Cloudy | 0 to 3 mph SW | 2% |
| Tuesday | 72°F | Sunny | 1 to 5 mph NNW | 5% |
Forecast source: National Weather Service (api.weather.gov) for San Miguel (37.887, -122.037). Updated through the day.
Growing snapshot for San Miguel
Last spring frost
Mar 8
First fall frost
Dec 22
Growing season
282 days
Hardiness zone
9b
More local growing data for San Miguel: nearby ZIP 94596 weather · frost dates · planting calendar · California frost dates
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Mountain View
Climate data from the nearest NOAA station, Mt Diablo Junction, Ca (5.8 mi from San Miguel). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.