ZIP 19801 Zone 7b
Delaware · USDA zone 7b, average annual extreme minimum 5°F to 10°F.
Nearest qualified station: WILMINGTON PORTER RSCH, DE US (USC00079605), 3.5 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% | March 26 | Earlier date. A last 32°F on or after this day is common. |
| 50% | April 7 | Median. |
| 10% | April 24 | 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 21 | Earlier date. A first 32°F on or before this day is uncommon. |
| 50% | November 4 | Median. |
| 90% | November 19 | 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% | 229 |
| 50% | 209 |
| 90% | 189 |
28°F threshold
| 10% | 50% | 90% | |
|---|---|---|---|
| Last, on or after | April 10 | March 29 | March 13 |
| First, on or before | November 1 | November 15 | December 2 |
| Season at least | 254 days | 232 days | 213 days |
36°F threshold
| 10% | 50% | 90% | |
|---|---|---|---|
| Last, on or after | May 7 | April 20 | April 6 |
| First, on or before | October 9 | October 24 | November 6 |
| Season at least | 204 days | 185 days | 165 days |
Station WILMINGTON PORTER RSCH, DE US (USC00079605). 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 82.3 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.