San Patricio, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 62.4 °F (low) to 82.2 °F (high). Annual precipitation averages 29.2 Inches. San Patricio is located in USDA Plant Hardiness Zone 9b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 46.1 °F | 66.7 °F | 1.48 in. |
| February | 50.0 °F | 70.8 °F | 1.41 in. |
| March | 56.4 °F | 75.8 °F | 2.22 in. |
| April | 62.4 °F | 82.4 °F | 1.83 in. |
| May | 69.8 °F | 87.5 °F | 3.08 in. |
| June | 74.4 °F | 92.7 °F | 3.22 in. |
| July | 75.4 °F | 94.6 °F | 2.99 in. |
| August | 75.6 °F | 96.0 °F | 2.41 in. |
| September | 72.2 °F | 91.1 °F | 4.53 in. |
| October | 64.0 °F | 85.1 °F | 2.6 in. |
| November | 54.8 °F | 75.5 °F | 1.7 in. |
| December | 47.9 °F | 68.7 °F | 1.75 in. |
| Annual | 62.4 °F | 82.2 °F | 29.22 in. |
| Average First Frost Date | Frost Rare |
| Average Last Frost Date | |
| Average Days With Frost | Frost Rare |
| Plant Hardiness Zone | Zone 9b : 25°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 9a : 20°F to 25°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |