Rockport, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 18.7 °C (low) to 25.6 °C (high). Annual precipitation averages 912.1 Millimeters. Rockport is located in USDA Plant Hardiness Zone 9b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 9.3 °C | 17.7 °C | 64.26 mm |
| February | 11.3 °C | 19.3 °C | 48.26 mm |
| March | 14.8 °C | 22 °C | 62.99 mm |
| April | 18.4 °C | 25.2 °C | 50.29 mm |
| May | 22.5 °C | 28.1 °C | 86.36 mm |
| June | 25.5 °C | 30.8 °C | 96.27 mm |
| July | 26.2 °C | 31.6 °C | 75.44 mm |
| August | 25.9 °C | 32.2 °C | 64.26 mm |
| September | 24 °C | 31.1 °C | 140.72 mm |
| October | 20.4 °C | 27.7 °C | 95.76 mm |
| November | 14.9 °C | 22.9 °C | 77.47 mm |
| December | 10.6 °C | 19.1 °C | 50.04 mm |
| Annual | 18.7 °C | 25.6 °C | 912.12 mm |
| Average First Frost Date | Frost Rare |
| Average Last Frost Date | |
| Average Days With Frost | Frost Rare |
| Plant Hardiness Zone | Zone 9b : -3.9°C to -1.1°C |
| Plant Hardiness Zone - 2012 | Zone 9b : -3.9°C to -1.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |