| 2023 Hardiness Zone: | Zone 10a: 30°F to 35°F | |
| 2012 Hardiness Zone: | Zone 9b: 25°F to 30°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: | 34e - Lower Rio Grande Valley | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | 151 - 180 days Over 86°F |
Annual Climate Data for ZIP Code 78552 - Harlingen, 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 | 71 | 64 | 57 | 50 | 63 |
| Avg Max Temp (°F) | 69 | 73 | 80 | 84 | 89 | 93 | 95 | 95 | 92 | 86 | 77 | 70 | 84 |
| Avg Precip (In.) | 1.45 | 1.7 | 1.2 | 2.06 | 2.76 | 2.92 | 1.86 | 2.83 | 4.91 | 2.89 | 1.41 | 1.32 | 27.28 |