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Will it freeze in San Luis in the next 7 nights?
No overnight lows at or below 32°F are forecast in San Luis during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 56°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM MST to Fri, Nov 6, 6:00 AM MST.
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
- Fri, Nov 6 62°F Above 36°F · Clear
- Sat, Nov 7 62°F Above 36°F · Clear
- Sun, Nov 8 62°F Above 36°F · Mostly Clear
- Mon, Nov 9 61°F Above 36°F · Mostly Clear
- Tue, Nov 10 60°F Above 36°F · Mostly Clear
- Wed, Nov 11 59°F Above 36°F · Mostly Clear
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
Most years have no 28°F hard freeze at Yuma Quartermaster Depot, 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 25 · Jan 28 · Feb 28 | Nov 29 · Dec 16 · Jan 5 | 324 days |
| 32°F freeze | Dec 17 · Jan 8 · Feb 19 | Dec 11 · Dec 28 · Feb 7 | 362 days |
| 28°F hard freeze | Dec 19 · Jan 1 · Feb 16 | Dec 16 · Dec 31 · Feb 10 | 365 days |
Average high temperature by month
1991–2020 normals at Yuma Quartermaster Depot
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, AZ come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Yuma Quartermaster Depot (station USC00029656, elevation 160 ft), 18 mi from San Luis. 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
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Somerton, AZ | 8.1 mi | Jan 8 | Dec 28 |
| Yuma, AZ | 12 mi | Jan 8 | Dec 28 |
| Holtville, CA | 44 mi | Jan 3 | Dec 27 |
| Calexico, CA | 47 mi | Jan 3 | Dec 27 |
| El Centro, CA | 53 mi | Jan 3 | Dec 27 |
| Imperial, CA | 55 mi | Jan 14 | Dec 24 |
| Brawley, CA | 58 mi | Jan 16 | Dec 19 |
| Calipatria, CA | 65 mi | Jan 16 | Dec 19 |
| Blythe, CA | 81 mi | Jan 25 | Dec 12 |
| Coachella, CA | 117 mi | rare | rare |
Frequently asked questions
When is the last frost in San Luis?
On average, the last spring frost (32°F) in San Luis is around January 8. In about 1 year in 10 it comes after February 19, and in 9 years in 10 it comes after December 17.
When is the first frost in San Luis?
The first fall frost (32°F) usually arrives around December 28. There’s a 10% chance of a freeze by December 11 and a 90% chance by February 7.
Can it frost in San Luis 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 28.
What growing zone is San Luis?
San Luis is in USDA Plant Hardiness Zone 10a (average annual extreme minimum temperature 30 to 35°F), based on the 2023 USDA map for ZIP code 85336. See growing zones in Arizona.
More: all Arizona frost dates · Arizona growing zones · UV index today in San Luis · frost vs. freeze