| 2023 Hardiness Zone: | Zone 5b: -15°F to -10°F |
| 2012 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 5a: -20F to -15F |
| Average First Frost Date: | Oct. 11 - Oct. 20 |
| Average Last Frost Date: | Apr. 21 - Apr. 30 |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers |
| Ecoregion: | 47f - Rolling Loess Prairies |
| Heat Zone Days: | 1 - 7 days Over 86°F |
Annual Climate Data for ZIP Code 50208 - Newton, IA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 9 | 14 | 26 | 37 | 50 | 59 | 64 | 62 | 52 | 40 | 27 | 15 | 38 |
| Avg Max Temp (°F) | 29 | 35 | 48 | 61 | 73 | 82 | 86 | 84 | 77 | 65 | 47 | 33 | 60 |
| Avg Precip (In.) | .96 | 1.1 | 2.16 | 3.34 | 4.55 | 4.55 | 4.06 | 4.13 | 3.57 | 2.75 | 2.26 | 1.15 | 34.57 |