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Will it freeze in Brentwood in the next 7 nights?
No overnight lows at or below 32°F are forecast in Brentwood during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 50°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 50°F Above 36°F · Mostly Clear
- Fri, Nov 6 49°F Above 36°F · Clear
- Sat, Nov 7 51°F Above 36°F · Mostly Clear
- Sun, Nov 8 52°F Above 36°F · Partly Cloudy
- Mon, Nov 9 52°F Above 36°F · Mostly Clear
- Tue, Nov 10 52°F Above 36°F · Partly Cloudy
- Wed, Nov 11 52°F Above 36°F · Slight 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 Brentwood
Most years have no 28°F hard freeze at Antioch Pumping Plt #3, 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 11 · Feb 8 · Mar 12 | Nov 18 · Dec 4 · Dec 28 | 299 days |
| 32°F freeze | Dec 20 · Jan 12 · Feb 1 | Nov 29 · Dec 19 · Jan 12 | 343 days |
| 28°F hard freeze | Dec 16 · Jan 2 · Jan 22 | Dec 9 · Dec 29 · Jan 16 | 365 days |
Average high temperature by month
1991–2020 normals at Antioch Pumping Plt #3
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 Brentwood, CA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Antioch Pumping Plt #3 (station USC00040232, elevation 60 ft), 3.8 mi from Brentwood. 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 Brentwood
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Oakley, CA | 4.3 mi | Jan 12 | Dec 19 |
| Antioch, CA | 5.0 mi | Jan 12 | Dec 19 |
| Pittsburg, CA | 11 mi | Jan 12 | Dec 19 |
| Clayton, CA | 12 mi | Mar 8 | Dec 22 |
| Mountain House, CA | 15 mi | Jan 19 | Dec 10 |
| Concord, CA | 16 mi | Jan 9 | Dec 14 |
| Danville, CA | 16 mi | Mar 8 | Dec 22 |
| San Ramon, CA | 17 mi | Mar 8 | Dec 22 |
| Rio Vista, CA | 17 mi | Jan 12 | Dec 19 |
| Livermore, CA | 17 mi | Feb 15 | Dec 2 |
Frequently asked questions
When is the last frost in Brentwood?
On average, the last spring frost (32°F) in Brentwood is around January 12. In about 1 year in 10 it comes after February 1, and in 9 years in 10 it comes after December 20.
When is the first frost in Brentwood?
The first fall frost (32°F) usually arrives around December 19. There’s a 10% chance of a freeze by November 29 and a 90% chance by January 12.
Can it frost in Brentwood 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 8.
What growing zone is Brentwood?
Brentwood 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 94513. See growing zones in California.
More: all California frost dates · California growing zones · UV index today in Brentwood · frost vs. freeze