| 2023 Hardiness Zone: | Zone 8a: 10°F to 15°F |
| 2012 Hardiness Zone: | Zone 7b: 5°F to 10°F |
| 1990 Hardiness Zone: | Zone 7a: 0F to 5F |
| Average First Frost Date: | Nov. 1 - Nov. 10 |
| Average Last Frost Date: | Apr. 11 - Apr. 20 |
| Koppen-Geiger Climate Zone: | Cfa - Humid Subtropical Climate |
| Ecoregion: | 63b - Chesapeake-Pamlico Lowlands and Tidal Marshes |
| Heat Zone Days: | 31 - 45 days Over 86°F |
Annual Climate Data for ZIP Code 21638 - Grasonville, MD | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 25 | 27 | 35 | 43 | 53 | 62 | 66 | 65 | 58 | 46 | 38 | 30 | 46 |
| Avg Max Temp (°F) | 43 | 47 | 56 | 66 | 76 | 84 | 88 | 86 | 80 | 69 | 58 | 48 | 67 |
| Avg Precip (In.) | 3.79 | 3 | 4.05 | 3.33 | 4.23 | 3.67 | 3.99 | 3.88 | 4.04 | 3.38 | 3.36 | 3.53 | 44.24 |