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Will it freeze in American Canyon in the next 7 nights?
No overnight lows at or below 32°F are forecast in American Canyon during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 46°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM PST to Fri, Nov 6, 6:00 AM PST.
No nights at or below 36°F in the National Weather Service forecast for the next 7 nights.
- Tonight 46°F Above 36°F · Mostly Clear
- Fri, Nov 6 46°F Above 36°F · Mostly Clear
- Sat, Nov 7 47°F Above 36°F · Mostly Clear then Patchy Fog
- Sun, Nov 8 48°F Above 36°F · Patchy Fog
- Mon, Nov 9 47°F Above 36°F · Mostly Clear then Patchy Fog
- Tue, Nov 10 49°F Above 36°F · Partly Cloudy then Slight Chance Light Rain
- Wed, Nov 11 49°F Above 36°F · Chance Light Rain
Overnight lows from the National Weather Service forecast for this location. This covers the available forecast window, not the first freeze of the whole season. Frost can form above 32°F on clear, calm nights.
Frost and freeze probabilities
Freeze dates shift from year to year. Spring percentages describe the chance of a freeze after the stated date; fall percentages describe the chance of a freeze by that date. The 10% spring date is the cautious one: a later freeze happens about 1 year in 10.
These dates describe historical probabilities, not this year’s forecast or the earliest and latest possible freezes. Different weather stations or probability thresholds can produce different published dates for the same city.
Average first hard freeze in American Canyon
The median first fall hard-freeze date (28°F) is December 5, from NOAA’s 1991–2020 Climate Normals at Napa County Airport. This is the 50% probability date, not a forecast for this year.
| Temperature | Last spring date 90% · 50% · 10% chance of a later freeze | First fall date 10% · 50% · 90% chance of an earlier freeze | Season |
|---|---|---|---|
| 36°F frost possible | Mar 17 · Apr 17 · May 9 | Oct 16 · Nov 4 · Nov 22 | 199 days |
| 32°F freeze | Jan 26 · Mar 5 · Apr 16 | Nov 3 · Nov 21 · Dec 13 | 256 days |
| 28°F hard freeze | Dec 20 · Jan 23 · Feb 28 | Nov 16 · Dec 5 · Jan 11 | 323 days |
Average high temperature by month
1991–2020 normals at Napa County Airport
Average low temperature by month
Months with lows near or below freezing carry frost risk
Where these frost dates come from
The frost dates for American Canyon, CA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Napa County Airport (station USW00093227, elevation 14 ft), 2.5 mi from American Canyon. Local conditions (valleys, hilltops, distance to water, city heat) can shift frost dates by days or weeks. The hardiness zone is from the 2023 USDA Plant Hardiness Zone Map (USDA ARS and Oregon State University PRISM). See our methodology.
Frost dates near American Canyon
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Vallejo, CA | 5.0 mi | Jan 17 | Dec 27 |
| Napa, CA | 8.7 mi | Feb 12 | Dec 4 |
| Benicia, CA | 9.3 mi | Jan 17 | Dec 27 |
| Hercules, CA | 11 mi | Jan 17 | Dec 27 |
| Pinole, CA | 12 mi | rare | rare |
| Sonoma, CA | 13 mi | Mar 2 | Nov 27 |
| Fairfield, CA | 14 mi | Jan 15 | Dec 14 |
| Suisun City, CA | 14 mi | Jan 15 | Dec 14 |
| Martinez, CA | 15 mi | Feb 28 | Nov 22 |
| San Pablo, CA | 16 mi | rare | rare |
Frequently asked questions
When is the last frost in American Canyon?
On average, the last spring frost (32°F) in American Canyon is around March 5. In about 1 year in 10 it comes after April 16, and in 9 years in 10 it comes after January 26.
When is the first frost in American Canyon?
The first fall frost (32°F) usually arrives around November 21. There’s a 10% chance of a freeze by November 3 and a 90% chance by December 13.
Can it frost in American Canyon after the last frost date?
Yes. Frost can form on clear, calm nights even when the air stays above 32°F. Temperatures of 36°F or lower, cold enough for frost on exposed plants, have a 50% chance of occurring after April 17.
What growing zone is American Canyon?
American Canyon is in USDA Plant Hardiness Zone 9b (average annual extreme minimum temperature 25 to 30°F), based on the 2023 USDA map for ZIP code 94503. See growing zones in California.
More: all California frost dates · California growing zones · frost vs. freeze