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Will it freeze in Los Altos in the next 7 nights?
No overnight lows at or below 32°F are forecast in Los Altos 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 50°F Above 36°F · Mostly Clear
- Sat, Nov 7 50°F Above 36°F · Mostly Clear
- Sun, Nov 8 52°F Above 36°F · Partly Cloudy
- Mon, Nov 9 51°F Above 36°F · Mostly Clear
- Tue, Nov 10 52°F Above 36°F · Partly Cloudy then Slight Chance Light Rain
- Wed, Nov 11 52°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 Los Altos
Most years have no 28°F hard freeze at Moffett Federal Airfield, 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 3 · Feb 6 · Mar 6 | Nov 20 · Dec 6 · Dec 30 | 306 days |
| 32°F freeze | Dec 16 · Jan 6 · Feb 4 | Dec 3 · Dec 23 · Jan 16 | 353 days |
| 28°F hard freeze | Dec 16 · Jan 1 · Jan 22 | Dec 13 · Dec 31 · Jan 22 | 365 days |
Average high temperature by month
1991–2020 normals at Moffett Federal Airfield
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 Los Altos, CA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Moffett Federal Airfield (station USW00023244, elevation 39 ft), 3.7 mi from Los Altos. 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 Los Altos
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Los Altos Hills, CA | 2.5 mi | Mar 21 | Dec 15 |
| Mountain View, CA | 2.5 mi | Jan 6 | Dec 23 |
| Palo Alto, CA | 3.1 mi | Feb 1 | Dec 7 |
| Sunnyvale, CA | 4.3 mi | Jan 6 | Dec 23 |
| Cupertino, CA | 4.3 mi | Jan 6 | Dec 23 |
| Santa Clara, CA | 6.8 mi | Jan 12 | Dec 22 |
| East Palo Alto, CA | 6.8 mi | Feb 1 | Dec 7 |
| Saratoga, CA | 8.1 mi | Feb 2 | Dec 6 |
| Menlo Park, CA | 8.1 mi | Feb 1 | Dec 7 |
| Atherton, CA | 8.7 mi | Jan 17 | Dec 12 |
Frequently asked questions
When is the last frost in Los Altos?
On average, the last spring frost (32°F) in Los Altos is around January 6. In about 1 year in 10 it comes after February 4, and in 9 years in 10 it comes after December 16.
When is the first frost in Los Altos?
The first fall frost (32°F) usually arrives around December 23. There’s a 10% chance of a freeze by December 3 and a 90% chance by January 16.
Can it frost in Los Altos 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 6.
What growing zone is Los Altos?
Los Altos 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 94040. See growing zones in California.
More: all California frost dates · California growing zones · UV index today in Los Altos · frost vs. freeze