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Will it freeze in Sierra Vista in the next 7 nights?
No overnight lows at or below 32°F are forecast in Sierra Vista 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 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 50°F Above 36°F · Mostly Clear
- Fri, Nov 6 50°F Above 36°F · Chance Rain Showers
- Sat, Nov 7 48°F Above 36°F · Mostly Clear
- Sun, Nov 8 47°F Above 36°F · Mostly Clear
- Mon, Nov 9 50°F Above 36°F · Mostly Clear
- Tue, Nov 10 50°F Above 36°F · Mostly Clear
- Wed, Nov 11 49°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 Sierra Vista
The median first fall hard-freeze date (28°F) is November 21, from NOAA’s 1991–2020 Climate Normals at Sierra Vista. 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 | Apr 5 · Apr 20 · May 4 | Oct 15 · Oct 30 · Nov 12 | 191 days |
| 32°F freeze | Mar 15 · Apr 5 · Apr 21 | Oct 23 · Nov 9 · Nov 23 | 216 days |
| 28°F hard freeze | Feb 21 · Mar 15 · Apr 5 | Nov 4 · Nov 21 · Dec 5 | 248 days |
Average high temperature by month
1991–2020 normals at Sierra Vista
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 Sierra Vista, AZ come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Sierra Vista (station USC00027880, elevation 4,606 ft), 2.8 mi from Sierra Vista. 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 Sierra Vista
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Benson, AZ | 24 mi | Apr 12 | Nov 1 |
| Nogales, AZ | 39 mi | Mar 20 | Nov 17 |
| Sahuarita, AZ | 46 mi | Feb 25 | Nov 27 |
| Douglas, AZ | 47 mi | Mar 18 | Nov 13 |
| Tucson, AZ | 52 mi | Feb 5 | Dec 9 |
| Oro Valley, AZ | 71 mi | Apr 2 | Nov 11 |
| Marana, AZ | 79 mi | Apr 2 | Nov 11 |
| Thatcher, AZ | 92 mi | Mar 25 | Nov 9 |
| Safford, AZ | 94 mi | Mar 25 | Nov 9 |
| Eloy, AZ | 111 mi | Feb 24 | Nov 28 |
Frequently asked questions
When is the last frost in Sierra Vista?
On average, the last spring frost (32°F) in Sierra Vista is around April 5. In about 1 year in 10 it comes after April 21, and in 9 years in 10 it comes after March 15.
When is the first frost in Sierra Vista?
The first fall frost (32°F) usually arrives around November 9. There’s a 10% chance of a freeze by October 23 and a 90% chance by November 23.
Can it frost in Sierra Vista 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 April 20.
What growing zone is Sierra Vista?
Sierra Vista is in USDA Plant Hardiness Zone 8b (average annual extreme minimum temperature 15 to 20°F), based on the 2023 USDA map for ZIP code 85613. See growing zones in Arizona.
More: all Arizona frost dates · Arizona growing zones · UV index today in Sierra Vista · frost vs. freeze