| 2023 Hardiness Zone: | Zone 7a: 0°F to 5°F |
| 2012 Hardiness Zone: | Zone 6b: -5°F to 0°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: | Dfa - Humid Continental Hot Summers |
| Ecoregion: | 84d - Inner Coastal Plain |
| Heat Zone Days: | 8 - 14 days Over 86°F |
Annual Climate Data for ZIP Code 08850 - Milltown, NJ | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 21 | 23 | 31 | 39 | 49 | 59 | 64 | 62 | 55 | 43 | 35 | 26 | 42 |
| Avg Max Temp (°F) | 38 | 41 | 50 | 61 | 72 | 80 | 85 | 84 | 77 | 65 | 54 | 43 | 63 |
| Avg Precip (In.) | 4.02 | 2.92 | 4.08 | 4.01 | 4.56 | 3.78 | 4.95 | 4.39 | 4.41 | 3.5 | 3.92 | 3.84 | 48.39 |