ZIP 60201 Zone 6a
Illinois · USDA zone 6a, average annual extreme minimum -10°F to -5°F.
Nearest qualified station: CHICAGO BOTANIC GARDEN, IL US (USC00111497), 7.6 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% | April 11 | Earlier date. A last 32°F on or after this day is common. |
| 50% | April 26 | Median. |
| 10% | May 11 | 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% | October 5 | Earlier date. A first 32°F on or before this day is uncommon. |
| 50% | October 21 | Median. |
| 90% | November 2 | 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% | 197 |
| 50% | 176 |
| 90% | 155 |
28°F threshold
| 10% | 50% | 90% | |
|---|---|---|---|
| Last, on or after | April 28 | April 13 | March 31 |
| First, on or before | October 17 | November 1 | November 14 |
| Season at least | 222 days | 202 days | 179 days |
36°F threshold
| 10% | 50% | 90% | |
|---|---|---|---|
| Last, on or after | May 26 | May 8 | April 24 |
| First, on or before | September 28 | October 10 | October 24 |
| Season at least | 174 days | 154 days | 135 days |
Station CHICAGO BOTANIC GARDEN, IL US (USC00111497). Completeness flag S, 29 years used for the 32°F dates. NCEI’s annual probability of at least one day at or below 32°F is 100%. Freeze dates are conditional on that threshold occurring. Elevation 192 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.