| 2023 Hardiness Zone: | Zone 7b: 5°F to 10°F Zone 7a: 0°F to 5°F | |
| 2012 Hardiness Zone: | Zone 6b: -5°F to 0°F Zone 7a: 0°F to 5°F | |
| 1990 Hardiness Zone: | Zone 6b: -5F to 0F | |
| Average First Frost Date: | Oct. 11 - Oct. 20 | |
| Average Last Frost Date: | May 1 - May 10 | |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers | |
| Ecoregion: | 64c - Piedmont Uplands | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | 15 - 30 days Over 86°F |
Annual Climate Data for ZIP Code 21754 - Ijamsville, MD | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 23 | 25 | 33 | 41 | 51 | 60 | 65 | 63 | 56 | 44 | 35 | 27 | 44 |
| Avg Max Temp (°F) | 41 | 45 | 54 | 66 | 75 | 83 | 87 | 85 | 78 | 68 | 56 | 45 | 65 |
| Avg Precip (In.) | 3.36 | 2.69 | 3.76 | 3.41 | 4.51 | 4.01 | 3.72 | 3.22 | 4.09 | 3.62 | 3.38 | 3.21 | 42.97 |