| 2023 Hardiness Zone: | Zone 9a: 20°F to 25°F | |
| 2012 Hardiness Zone: | Zone 8b: 15°F to 20°F Zone 9a: 20°F to 25°F | |
| 1990 Hardiness Zone: | Zone 8b: 15F to 20F | |
| Average First Frost Date: | Nov. 21 - Nov. 30 | |
| Average Last Frost Date: | Mar. 1 - Mar. 10 | |
| Koppen-Geiger Climate Zone: | Cfa - Humid Subtropical Climate | |
| Ecoregion: | 32a - Northern Blackland Prairie | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | 121 - 150 days Over 86°F |
Annual Climate Data for ZIP Code 78009 - Castroville, TX | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 38 | 42 | 49 | 56 | 64 | 70 | 71 | 71 | 67 | 58 | 48 | 41 | 56 |
| Avg Max Temp (°F) | 64 | 69 | 76 | 82 | 87 | 93 | 96 | 96 | 91 | 83 | 73 | 65 | 81 |
| Avg Precip (In.) | 1.37 | 1.71 | 1.84 | 2.58 | 3.79 | 3.95 | 1.69 | 2.62 | 2.67 | 3.49 | 1.96 | 1.61 | 29.29 |