ZIP 85021 Zone 9b
Arizona · USDA zone 9b, average annual extreme minimum 25°F to 30°F.
Nearest qualified station: PHOENIX DEER VALLEY MUNI AP, AZ US (USW00003184), 8.8 miles from the Census ZCTA internal point for this ZIP.
Outside the median season Growing seasonTicks: 10%, 50%, and 90%
Last 32°F in spring
NCEI’s probability is the chance the last spring minimum of 32°F or lower occurs on or after the date.
| Probability | Date | How to read it |
|---|---|---|
| 90% | December 16 | Earlier date. A last 32°F on or after this day is common. |
| 50% | January 8 | Median. |
| 10% | February 12 | Later date. A last 32°F on or after this day is uncommon. |
First 32°F in fall
NCEI’s probability is the chance the first autumn minimum of 32°F or lower occurs on or before the date.
| Probability | Date | How to read it |
|---|---|---|
| 10% | December 5 | Earlier date. A first 32°F on or before this day is uncommon. |
| 50% | December 25 | Median. |
| 90% | January 23 | Later date. A first 32°F on or before this day is common. |
32°F growing-season length
Days between the last spring 32°F and the first autumn 32°F. The figure is a length the season meets or exceeds at that probability, from NCEI, not a subtraction done on this site.
| Probability the season is at least this long | Days |
|---|---|
| 10% | 365 |
| 50% | 354 |
| 90% | 320 |
28°F threshold
| 10% | 50% | 90% | |
|---|---|---|---|
| Last, on or after | February 2 | January 8 | December 15 |
| First, on or before | December 14 | January 7 | February 1 |
| Season at least | 365 days | 365 days | 359 days |
36°F threshold
| 10% | 50% | 90% | |
|---|---|---|---|
| Last, on or after | March 2 | February 1 | January 1 |
| First, on or before | November 25 | December 11 | December 29 |
| Season at least | 347 days | 314 days | 279 days |
Station PHOENIX DEER VALLEY MUNI AP, AZ US (USW00003184). Completeness flag R, 21 years used for the 32°F dates. NCEI’s annual probability of at least one day at or below 32°F is 70.2%. Freeze dates are conditional on that threshold occurring. Elevation 443.5 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.