| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 6b: -5°F to 0°F Zone 7a: 0°F to 5°F |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 6b: -5°F to 0°F |
| 1990 Hardiness Zone: | Zone 6a: -10F to -5F |
| Average First Frost Date: | Oct. 21 - Oct. 31 |
| Average Last Frost Date: | May 1 - May 10 |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers |
| Ecoregion: | 70c - Pittsburgh Low Plateau |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 15478 - Smithfield, PA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 19 | 21 | 29 | 37 | 47 | 56 | 60 | 59 | 52 | 40 | 32 | 25 | 40 |
| Avg Max Temp (°F) | 38 | 41 | 51 | 62 | 72 | 79 | 83 | 81 | 75 | 64 | 52 | 42 | 62 |
| Avg Precip (In.) | 3.03 | 2.69 | 3.59 | 3.67 | 4.31 | 4.26 | 4.5 | 3.89 | 3.6 | 2.81 | 3.39 | 3.08 | 42.84 |