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Will it freeze in San Luis Obispo in the next 7 nights?
No overnight lows at or below 32°F are forecast in San Luis Obispo during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 56°F. Above 36°F.
NWS forecast period: Fri, Nov 6, 6:00 PM PST to Sat, Nov 7, 6:00 AM PST.
No nights at or below 36°F in the National Weather Service forecast for the next 7 nights.
- Tonight 56°F Above 36°F · Mostly Clear
- Sat, Nov 7 56°F Above 36°F · Mostly Clear
- Sun, Nov 8 54°F Above 36°F · Mostly Clear
- Mon, Nov 9 54°F Above 36°F · Mostly Clear
- Tue, Nov 10 55°F Above 36°F · Mostly Clear
- Wed, Nov 11 55°F Above 36°F · Partly Cloudy then Slight Chance Light Rain
- Thu, Nov 12 54°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 San Luis Obispo
Most years have no 28°F hard freeze at San Luis Obispo Airport, 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 | Feb 6 · Mar 17 · Apr 16 | Nov 3 · Nov 24 · Dec 11 | 250 days |
| 32°F freeze | Dec 23 · Jan 31 · Mar 7 | Nov 20 · Dec 11 · Jan 13 | 319 days |
| 28°F hard freeze | Dec 11 · Jan 3 · Feb 1 | Dec 4 · Dec 28 · Jan 26 | 365 days |
Average high temperature by month
1991–2020 normals at San Luis Obispo Airport
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 Luis Obispo, CA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: San Luis Obispo Airport (station USW00093206, elevation 200 ft), 2.5 mi from San Luis Obispo. 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 Luis Obispo
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Pismo Beach, CA | 8.1 mi | Feb 1 | Jan 4 |
| Grover Beach, CA | 11 mi | Feb 1 | Jan 4 |
| Arroyo Grande, CA | 11 mi | Feb 1 | Jan 4 |
| Morro Bay, CA | 13 mi | rare | rare |
| Atascadero, CA | 15 mi | Mar 15 | Nov 10 |
| Guadalupe, CA | 22 mi | Feb 4 | Dec 13 |
| Paso Robles, CA | 25 mi | Mar 15 | Nov 10 |
| Santa Maria, CA | 26 mi | Feb 4 | Dec 13 |
| Lompoc, CA | 43 mi | Jan 20 | Dec 19 |
| Buellton, CA | 52 mi | Apr 11 | Nov 8 |
Frequently asked questions
When is the last frost in San Luis Obispo?
On average, the last spring frost (32°F) in San Luis Obispo is around January 31. In about 1 year in 10 it comes after March 7, and in 9 years in 10 it comes after December 23.
When is the first frost in San Luis Obispo?
The first fall frost (32°F) usually arrives around December 11. There’s a 10% chance of a freeze by November 20 and a 90% chance by January 13.
Can it frost in San Luis Obispo 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 17.
What growing zone is San Luis Obispo?
San Luis Obispo 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 93410. See growing zones in California.
More: all California frost dates · California growing zones · UV index today in San Luis Obispo · frost vs. freeze