ZIP 21740 Zone 7a
Maryland · USDA zone 7a, average annual extreme minimum 0°F to 5°F.
Nearest qualified station: HAGERSTOWN WASHINGTON CO AP, MD US (USW00093706), 5.3 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 25 | Earlier date. A last 32°F on or after this day is common. |
| 50% | April 7 | Median. |
| 10% | April 21 | 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 22 | Earlier date. A first 32°F on or before this day is uncommon. |
| 50% | November 4 | Median. |
| 90% | November 17 | 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% | 228 |
| 50% | 209 |
| 90% | 189 |
28°F threshold
| 10% | 50% | 90% | |
|---|---|---|---|
| Last, on or after | April 8 | March 28 | March 13 |
| First, on or before | November 1 | November 14 | December 2 |
| Season at least | 256 days | 232 days | 212 days |
36°F threshold
| 10% | 50% | 90% | |
|---|---|---|---|
| Last, on or after | May 7 | April 19 | April 6 |
| First, on or before | October 9 | October 23 | November 5 |
| Season at least | 206 days | 186 days | 165 days |
Station HAGERSTOWN WASHINGTON CO AP, MD US (USW00093706). Completeness flag R, 18 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 212.8 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.