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Will it freeze in San Francisco in the next 7 nights?
No overnight lows at or below 32°F are forecast in San Francisco during the next 7 nights in the available NWS frost forecast.
Overnight: forecast low 53°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 2:00 AM PST to Thu, Nov 5, 6:00 AM PST.
No nights at or below 36°F in the National Weather Service forecast for the next 7 nights.
- Overnight 53°F Above 36°F · Partly Cloudy
- Tonight 54°F Above 36°F · Mostly Clear
- Fri, Nov 6 53°F Above 36°F · Mostly Clear
- Sat, Nov 7 54°F Above 36°F · Mostly Clear then Patchy Fog
- Sun, Nov 8 56°F Above 36°F · Partly Cloudy
- Mon, Nov 9 56°F Above 36°F · Partly Cloudy
- Tue, Nov 10 56°F Above 36°F · Partly Cloudy then 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 San Francisco
Most years have no 28°F hard freeze at San Francisco Oceanside, 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 | Dec 11 · Jan 15 · Apr 7 | Nov 28 · Dec 26 · Feb 22 | 347 days |
| 32°F freeze | Dec 2 · Dec 30 · Mar 13 | Nov 26 · Dec 25 · Feb 13 | 365 days |
| 28°F hard freeze | rare in most years | rare in most years | 365 days |
Average high temperature by month
1991–2020 normals at San Francisco Oceanside
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 San Francisco, CA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: San Francisco Oceanside (station USC00047767, elevation 8 ft), 5.9 mi from San Francisco. 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 San Francisco
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Daly City, CA | 6.2 mi | rare | rare |
| Sausalito, CA | 6.8 mi | Jan 16 | Dec 18 |
| Emeryville, CA | 7.5 mi | rare | rare |
| Tiburon, CA | 8.1 mi | rare | rare |
| Berkeley, CA | 8.7 mi | rare | rare |
| South San Francisco, CA | 8.7 mi | rare | rare |
| Alameda, CA | 9.3 mi | Jan 7 | Dec 23 |
| Albany, CA | 9.3 mi | rare | rare |
| Oakland, CA | 11 mi | Jan 7 | Dec 23 |
| San Bruno, CA | 11 mi | rare | rare |
Frequently asked questions
When is the last frost in San Francisco?
San Francisco doesn’t reach 32°F in a typical year, according to NOAA’s 1991–2020 normals for the nearest station.
When is the first frost in San Francisco?
Freezes are uncommon here; check the 7-night forecast above during cold snaps.
Can it frost in San Francisco 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 January 15.
What growing zone is San Francisco?
San Francisco is in USDA Plant Hardiness Zone 10b (average annual extreme minimum temperature 35 to 40°F), based on the 2023 USDA map for ZIP code 94102. See growing zones in California.
More: all California frost dates · California growing zones · UV index today in San Francisco · frost vs. freeze