| 2023 Hardiness Zone: | Zone 5b: -15°F to -10°F | |
| 2012 Hardiness Zone: | Zone 5a: -20°F to -15°F | |
| 1990 Hardiness Zone: | Zone 5a: -20F to -15F | |
| 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: | 47b - Des Moines Lobe | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | 8 - 14 days Over 86°F |
Annual Climate Data for ZIP Code 50009 - Altoona, IA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 10 | 15 | 27 | 38 | 50 | 60 | 64 | 62 | 52 | 41 | 27 | 15 | 38 |
| Avg Max Temp (°F) | 28 | 35 | 47 | 60 | 72 | 81 | 85 | 83 | 76 | 64 | 46 | 33 | 59 |
| Avg Precip (In.) | .87 | 1.04 | 2.15 | 3.38 | 4.37 | 4.82 | 4.21 | 4.2 | 3.28 | 2.59 | 2.07 | 1.15 | 34.14 |