American Canyon, CA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for American Canyon, a city in Napa County, California.
Today
80°F
Mostly Sunny
Mostly sunny. High near 80, with temperatures falling to around 78 in the afternoon. Southwest wind 3 to 10 mph.
7-day forecast for American Canyon
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 80°F | Mostly Sunny | 3 to 10 mph SW | 0% |
| Tonight | 56°F | Partly Cloudy | 3 to 8 mph SW | 0% |
| Sunday | 72°F | Mostly Cloudy | 3 to 8 mph SW | 1% |
| Sunday Night | 55°F | Mostly Cloudy | 7 mph SW | 1% |
| Monday | 73°F | Mostly Sunny | 6 to 10 mph SW | 0% |
| Monday Night | 55°F | Partly Cloudy | 5 to 10 mph SW | 0% |
| Tuesday | 75°F | Mostly Sunny | 5 to 9 mph SW | 0% |
| Tuesday Night | 55°F | Mostly Clear then Patchy Fog | 1 to 9 mph WSW | 0% |
| Wednesday | 85°F | Patchy Fog then Mostly Sunny | 1 to 6 mph WSW | 0% |
| Wednesday Night | 58°F | Partly Cloudy | 0 to 6 mph WNW | 0% |
| Thursday | 86°F | Mostly Sunny | 0 to 8 mph WSW | 0% |
| Thursday Night | 58°F | Partly Cloudy | 2 to 8 mph WSW | 0% |
| Friday | 78°F | Mostly Sunny | 3 to 9 mph SW | 0% |
| Friday Night | 56°F | Partly Cloudy | 3 to 9 mph SW | 1% |
Forecast source: National Weather Service (api.weather.gov) for American Canyon (38.179, -122.260). Updated through the day.
Growing snapshot for American Canyon
Last spring frost
Mar 5
First fall frost
Nov 21
Growing season
256 days
Hardiness zone
9b
More local growing data for American Canyon: nearby ZIP 94503 weather · frost dates · planting calendar · California frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Napa Co Ap, Ca (3.7 mi from American Canyon). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.