| 2023 Hardiness Zone: | Zone 8a: 10°F to 15°F |
| 2012 Hardiness Zone: | Zone 8a: 10°F to 15°F Zone 7b: 5°F to 10°F |
| 1990 Hardiness Zone: | Zone 7b: 5F to 10F |
| Average First Frost Date: | Nov. 11 - Nov. 20 |
| Average Last Frost Date: | Mar. 21 - Mar. 31 |
| Koppen-Geiger Climate Zone: | Cfa - Humid Subtropical Climate |
| Ecoregion: | 33a - Northern Post Oak Savanna |
| Heat Zone Days: | 91 - 120 days Over 86°F |
Annual Climate Data for ZIP Code 75021 - Denison, TX | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 30 | 35 | 43 | 51 | 60 | 68 | 72 | 71 | 64 | 53 | 42 | 33 | 52 |
| Avg Max Temp (°F) | 51 | 57 | 65 | 73 | 80 | 88 | 93 | 93 | 86 | 76 | 63 | 54 | 73 |
| Avg Precip (In.) | 2.07 | 2.6 | 3.47 | 3.57 | 5.41 | 4.58 | 2.55 | 2.35 | 4.18 | 4.72 | 3.57 | 2.81 | 41.89 |