| 2023 Hardiness Zone: | 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. 1 - Oct. 10 | |
| Average Last Frost Date: | May 1 - May 10 | |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers | |
| Ecoregion: | 64a - Triassic Lowlands | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | 8 - 14 days Over 86°F |
Annual Climate Data for ZIP Code 19438 - Harleysville, PA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 20 | 22 | 30 | 39 | 49 | 58 | 63 | 61 | 53 | 41 | 34 | 25 | 41 |
| Avg Max Temp (°F) | 38 | 41 | 50 | 61 | 72 | 80 | 85 | 83 | 76 | 65 | 54 | 43 | 62 |
| Avg Precip (In.) | 3.75 | 2.73 | 3.62 | 3.73 | 4.37 | 3.71 | 4.31 | 4.14 | 4.31 | 3.35 | 3.71 | 3.49 | 45.23 |