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Will it freeze in Fairfield in the next 7 nights?
No overnight lows at or below 32°F are forecast in Fairfield during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 49°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 49°F Above 36°F · Mostly Clear
- Fri, Nov 6 49°F Above 36°F · Clear
- Sat, Nov 7 50°F Above 36°F · Mostly Clear
- Sun, Nov 8 51°F Above 36°F · Partly Cloudy
- Mon, Nov 9 50°F Above 36°F · Mostly Clear
- Tue, Nov 10 51°F Above 36°F · Partly Cloudy then Slight Chance Light Rain
- Wed, Nov 11 51°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 Fairfield
Most years have no 28°F hard freeze at Fairfield, according to NOAA’s 1991–2020 Climate Normals. Check the short-term forecast above during cold snaps.
| 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 | Jan 23 · Feb 25 · Apr 4 | Nov 13 · Dec 1 · Dec 21 | 278 days |
| 32°F freeze | Dec 22 · Jan 15 · Feb 16 | Nov 29 · Dec 14 · Jan 9 | 336 days |
| 28°F hard freeze | Dec 13 · Dec 31 · Jan 19 | Dec 6 · Dec 24 · Jan 11 | 365 days |
Average high temperature by month
1991–2020 normals at Fairfield
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 Fairfield, CA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Fairfield (station USC00042934, elevation 40 ft), 2.1 mi from Fairfield. 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 Fairfield
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Suisun City, CA | 1.2 mi | Jan 15 | Dec 14 |
| Vacaville, CA | 7.5 mi | Feb 18 | Nov 28 |
| American Canyon, CA | 14 mi | Mar 5 | Nov 21 |
| Benicia, CA | 15 mi | Jan 17 | Dec 27 |
| Napa, CA | 15 mi | Feb 12 | Dec 4 |
| Vallejo, CA | 16 mi | Jan 17 | Dec 27 |
| Dixon, CA | 17 mi | Feb 10 | Dec 1 |
| Pittsburg, CA | 19 mi | Jan 12 | Dec 19 |
| Martinez, CA | 19 mi | Feb 28 | Nov 22 |
| Rio Vista, CA | 19 mi | Jan 12 | Dec 19 |
Frequently asked questions
When is the last frost in Fairfield?
On average, the last spring frost (32°F) in Fairfield is around January 15. In about 1 year in 10 it comes after February 16, and in 9 years in 10 it comes after December 22.
When is the first frost in Fairfield?
The first fall frost (32°F) usually arrives around December 14. There’s a 10% chance of a freeze by November 29 and a 90% chance by January 9.
Can it frost in Fairfield 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 February 25.
What growing zone is Fairfield?
Fairfield 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 94533. See growing zones in California.
More: all California frost dates · California growing zones · UV index today in Fairfield · frost vs. freeze