Baytown, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 61.8 °F (low) to 77.7 °F (high). Annual precipitation averages 59.6 Inches. Baytown is located in USDA Plant Hardiness Zone 9b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 44.8 °F | 62.2 °F | 4.63 in. |
| February | 48.5 °F | 65.4 °F | 3.51 in. |
| March | 54.8 °F | 71.1 °F | 3.76 in. |
| April | 61.5 °F | 76.7 °F | 4.35 in. |
| May | 69.1 °F | 83.0 °F | 5.58 in. |
| June | 74.9 °F | 88.7 °F | 6.01 in. |
| July | 76.7 °F | 90.7 °F | 4.68 in. |
| August | 76.2 °F | 91.5 °F | 6.39 in. |
| September | 72.0 °F | 87.4 °F | 5.7 in. |
| October | 63.5 °F | 80.2 °F | 5.61 in. |
| November | 53.4 °F | 71.1 °F | 4.8 in. |
| December | 46.7 °F | 64.0 °F | 4.53 in. |
| Annual | 61.8 °F | 77.7 °F | 59.55 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 |