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Will it freeze in Palo Alto in the next 7 nights?
No overnight lows at or below 32°F are forecast in Palo Alto 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 then Patchy Fog
- 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 Palo Alto
The median first fall hard-freeze date (28°F) is December 22, from NOAA’s 1991–2020 Climate Normals at Palo Alto. 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 | Feb 5 · Mar 11 · Apr 15 | Nov 3 · Nov 21 · Dec 8 | 252 days |
| 32°F freeze | Dec 28 · Feb 1 · Mar 4 | Nov 20 · Dec 7 · Jan 6 | 310 days |
| 28°F hard freeze | Dec 15 · Jan 4 · Feb 17 | Dec 3 · Dec 22 · Jan 25 | 358 days |
Average high temperature by month
1991–2020 normals at Palo Alto
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 Palo Alto, CA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Palo Alto (station USC00046646, elevation 25 ft), 3.2 mi from Palo Alto. 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 Palo Alto
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Los Altos Hills, CA | 1.9 mi | Mar 21 | Dec 15 |
| Los Altos, CA | 3.1 mi | Jan 6 | Dec 23 |
| Mountain View, CA | 3.7 mi | Jan 6 | Dec 23 |
| East Palo Alto, CA | 5.0 mi | Feb 1 | Dec 7 |
| Atherton, CA | 5.0 mi | Jan 17 | Dec 12 |
| Menlo Park, CA | 5.6 mi | Feb 1 | Dec 7 |
| Sunnyvale, CA | 6.2 mi | Jan 6 | Dec 23 |
| Woodside, CA | 6.8 mi | Feb 25 | Nov 25 |
| Cupertino, CA | 7.5 mi | Jan 6 | Dec 23 |
| Redwood City, CA | 9.3 mi | Jan 17 | Dec 12 |
Frequently asked questions
When is the last frost in Palo Alto?
On average, the last spring frost (32°F) in Palo Alto is around February 1. In about 1 year in 10 it comes after March 4, and in 9 years in 10 it comes after December 28.
When is the first frost in Palo Alto?
The first fall frost (32°F) usually arrives around December 7. There’s a 10% chance of a freeze by November 20 and a 90% chance by January 6.
Can it frost in Palo Alto 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 March 11.
What growing zone is Palo Alto?
Palo Alto 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 94304. See growing zones in California.
More: all California frost dates · California growing zones · UV index today in Palo Alto · frost vs. freeze