| 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: | Frost Rare |
| Average Last Frost Date: | Frost Rare |
| Koppen-Geiger Climate Zone: | Cfa - Humid Subtropical Climate |
| Ecoregion: | 34i - Laguna Madre Barrier Islands and Coastal Marshes |
| Heat Zone Days: | 121 - 150 days Over 86°F |
Annual Climate Data for ZIP Code 78578 - Port Isabel, TX | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 52 | 55 | 61 | 67 | 73 | 76 | 77 | 77 | 75 | 69 | 62 | 54 | 67 |
| Avg Max Temp (°F) | 67 | 70 | 75 | 79 | 84 | 88 | 90 | 90 | 88 | 83 | 76 | 69 | 80 |
| Avg Precip (In.) | 1.92 | 1.72 | 1.2 | 1.77 | 2.42 | 1.97 | 1.76 | 2.14 | 6.07 | 3.71 | 2.13 | 1.61 | 28.43 |