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Will it freeze in Sonoma in the next 7 nights?
No overnight lows at or below 32°F are forecast in Sonoma during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 44°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 44°F Above 36°F · Mostly Clear
- Fri, Nov 6 43°F Above 36°F · Clear
- Sat, Nov 7 43°F Above 36°F · Mostly Clear then Patchy Fog
- Sun, Nov 8 45°F Above 36°F · Partly Cloudy then Patchy Fog
- Mon, Nov 9 44°F Above 36°F · Mostly Clear then Areas Of Fog
- Tue, Nov 10 46°F Above 36°F · Partly Cloudy then Areas Of Fog
- Wed, Nov 11 45°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 Sonoma
The median first fall hard-freeze date (28°F) is December 14, from NOAA’s 1991–2020 Climate Normals at Sonoma. 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 14 · Apr 8 · Apr 29 | Oct 25 · Nov 8 · Nov 26 | 214 days |
| 32°F freeze | Jan 27 · Mar 2 · Apr 5 | Nov 6 · Nov 27 · Dec 21 | 270 days |
| 28°F hard freeze | Dec 20 · Jan 20 · Feb 22 | Nov 24 · Dec 14 · Jan 17 | 334 days |
Average high temperature by month
1991–2020 normals at Sonoma
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 Sonoma, CA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Sonoma (station USC00048351, elevation 97 ft), 0.6 mi from Sonoma. 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 Sonoma
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Napa, CA | 8.7 mi | Feb 12 | Dec 4 |
| Petaluma, CA | 9.9 mi | Feb 28 | Nov 25 |
| American Canyon, CA | 13 mi | Mar 5 | Nov 21 |
| Rohnert Park, CA | 14 mi | Feb 25 | Dec 1 |
| Cotati, CA | 14 mi | Feb 28 | Nov 25 |
| Novato, CA | 15 mi | Jan 11 | Dec 21 |
| St. Helena, CA | 16 mi | Feb 3 | Dec 4 |
| Vallejo, CA | 17 mi | Jan 17 | Dec 27 |
| Santa Rosa, CA | 17 mi | Feb 25 | Dec 1 |
| Hercules, CA | 21 mi | Jan 17 | Dec 27 |
Frequently asked questions
When is the last frost in Sonoma?
On average, the last spring frost (32°F) in Sonoma is around March 2. In about 1 year in 10 it comes after April 5, and in 9 years in 10 it comes after January 27.
When is the first frost in Sonoma?
The first fall frost (32°F) usually arrives around November 27. There’s a 10% chance of a freeze by November 6 and a 90% chance by December 21.
Can it frost in Sonoma 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 8.
What growing zone is Sonoma?
Sonoma 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 95476. See growing zones in California.
More: all California frost dates · California growing zones · frost vs. freeze