| 2023 Hardiness Zone: | Zone 7b: 5°F to 10°F |
| 2012 Hardiness Zone: | Zone 7a: 0°F to 5°F |
| 1990 Hardiness Zone: | Zone 6b: -5F to 0F |
| Average First Frost Date: | Oct. 21 - Oct. 31 |
| Average Last Frost Date: | Apr. 21 - Apr. 30 |
| Koppen-Geiger Climate Zone: | Cfa - Humid Subtropical Climate |
| Ecoregion: | 64c - Piedmont Uplands |
| Heat Zone Days: | 31 - 45 days Over 86°F |
Annual Climate Data for ZIP Code 20868 - Spencerville, MD | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 23 | 26 | 33 | 42 | 52 | 61 | 66 | 64 | 57 | 45 | 36 | 28 | 44 |
| Avg Max Temp (°F) | 41 | 45 | 55 | 66 | 75 | 82 | 87 | 85 | 78 | 67 | 56 | 46 | 65 |
| Avg Precip (In.) | 3.4 | 2.96 | 4.07 | 3.4 | 4.65 | 3.8 | 4.01 | 3.69 | 4.22 | 3.55 | 3.75 | 3.44 | 44.95 |