| 2023 Hardiness Zone: | Zone 10b: 35°F to 40°F Zone 10a: 30°F to 35°F |
| 2012 Hardiness Zone: | Zone 10a: 30°F to 35°F |
| 1990 Hardiness Zone: | Zone 9b: 25F to 30F |
| Average First Frost Date: | Jan. 21 - Jan. 31 |
| Average Last Frost Date: | Jan. 21 - Jan. 31 |
| Koppen-Geiger Climate Zone: | Cfa - Humid Subtropical Climate |
| Ecoregion: | 34f - Lower Rio Grande Alluvial Floodplain |
| Heat Zone Days: | 151 - 180 days Over 86°F |
Annual Climate Data for ZIP Code 78583 - Rio Hondo, TX | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 48 | 51 | 58 | 64 | 70 | 74 | 74 | 74 | 72 | 65 | 57 | 50 | 63 |
| Avg Max Temp (°F) | 69 | 73 | 79 | 84 | 88 | 92 | 95 | 95 | 91 | 85 | 77 | 70 | 83 |
| Avg Precip (In.) | 1.46 | 1.73 | 1.21 | 2.15 | 2.75 | 2.9 | 1.81 | 2.88 | 5.05 | 2.97 | 1.47 | 1.34 | 27.72 |