Frost dates for 85269Fountain Hills, AZ
The average last spring frost in Fountain Hills is January 6 and the average first fall frost is December 28, giving a typical growing season of about 356 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Jan 6
- Average first fall frost
- Dec 28
- Growing season
- 356 days
Safer after Feb 11 (1-in-10 risk)
Possible by Dec 4 (1-in-10 risk)
First frost typically in 55 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | Dec 31 · Jan 31 · Mar 1 | Nov 25 · Dec 14 · Jan 3 | 317 days | 98% |
| Frost / freeze (32°F) | Dec 14 · Jan 6 · Feb 11 | Dec 4 · Dec 28 · Jan 27 | 356 days | 63% |
| Hard freeze (28°F) | Dec 27 · Jan 9 · Jan 31 | Dec 26 · Jan 8 · Jan 31 | 365 days | 14% |
Where these dates come from
ZIP code 85269 is matched to the NOAA station Fountain Hills, AZ, 1.1 km away, at 1,580 ft elevation (31 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Fountain Hills, AZ (used) | 1,580 ft | Jan 6 | Dec 28 |
| Stewart Mtn Dam, AZ | 1,422 ft | Feb 13 | Dec 5 |
| Scottsdale Muni Ap, AZ | 1,473 ft | Jan 6 | Dec 26 |
| Pinnacle Peak, AZ | 2,565 ft | Jan 27 | Dec 21 |
Frost dates near Fountain Hills
- Fountain Hills, AZ 85268 · last Jan 6, first Dec 28
- Fort Mcdowell, AZ 85264 · last Jan 6, first Dec 28
- Scottsdale, AZ 85259 · last Jan 6, first Dec 26
- Rio Verde, AZ 85263 · last Jan 6, first Dec 28
- Mesa, AZ 85215 · last Feb 1, first Dec 10
- Phoenix, AZ 85054 · last Jan 6, first Dec 26
- Paradise Valley, AZ 85253 · last Jan 6, first Dec 26
- Tempe, AZ 85288 · last Feb 13, first Dec 5
Frequently asked questions
- When is the last frost in Fountain Hills, AZ?
- For ZIP code 85269, the average last spring frost (32°F) is January 6, based on NOAA 1991-2020 climate normals for the Fountain Hills, AZ weather station. There is a 1-in-10 chance of a frost after February 11.
- When is the first frost in Fountain Hills, AZ?
- The average first fall frost (32°F) is December 28. There is a 1-in-10 chance of frost by December 4, so tender plants are at risk from that point on.
- How long is the growing season in 85269?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 356 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.