Checking current alerts… View NWS forecast and alerts.
Will it freeze in San Jose in the next 7 nights?
No overnight lows at or below 32°F are forecast in San Jose during the next 7 nights in the available NWS frost forecast.
Overnight: forecast low 48°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 5:00 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 48°F Above 36°F · Patchy Fog
- Tonight 49°F Above 36°F · Mostly Clear
- Fri, Nov 6 49°F Above 36°F · Mostly Clear
- Sat, Nov 7 49°F Above 36°F · Mostly Clear
- Sun, Nov 8 50°F Above 36°F · Mostly Clear
- Mon, Nov 9 50°F Above 36°F · Mostly Clear
- Tue, Nov 10 51°F Above 36°F · Mostly Clear 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 Jose
Most years have no 28°F hard freeze at San Jose, 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 27 · Jan 26 · Feb 27 | Nov 22 · Dec 10 · Jan 4 | 318 days |
| 32°F freeze | Dec 14 · Jan 2 · Jan 23 | Dec 4 · Dec 25 · Jan 14 | 362 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 Jose
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 Jose, CA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: San Jose (station USC00047821, elevation 67 ft), 6.2 mi from San Jose. 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 Jose
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Campbell, CA | 7.5 mi | Feb 2 | Dec 6 |
| Los Gatos, CA | 9.3 mi | Feb 2 | Dec 6 |
| Santa Clara, CA | 9.9 mi | Jan 12 | Dec 22 |
| Milpitas, CA | 11 mi | Jan 12 | Dec 22 |
| Saratoga, CA | 12 mi | Feb 2 | Dec 6 |
| Cupertino, CA | 13 mi | Jan 6 | Dec 23 |
| Sunnyvale, CA | 13 mi | Jan 6 | Dec 23 |
| Morgan Hill, CA | 15 mi | Feb 24 | Nov 27 |
| Fremont, CA | 16 mi | rare | rare |
| Mountain View, CA | 16 mi | Jan 6 | Dec 23 |
Frequently asked questions
When is the last frost in San Jose?
On average, the last spring frost (32°F) in San Jose is around January 2. In about 1 year in 10 it comes after January 23, and in 9 years in 10 it comes after December 14.
When is the first frost in San Jose?
The first fall frost (32°F) usually arrives around December 25. There’s a 10% chance of a freeze by December 4 and a 90% chance by January 14.
Can it frost in San Jose 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 26.
What growing zone is San Jose?
San Jose 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 95121. See growing zones in California.
More: all California frost dates · California growing zones · UV index today in San Jose · frost vs. freeze