Westchester, Florida has a Tropical Monsoon climate (Köppen classification: Am). Average annual temperatures range from 20.6 °C (low) to 29 °C (high). Annual precipitation averages 1679.2 Millimeters. Westchester is located in USDA Plant Hardiness Zone 11a.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 14.9 °C | 24.6 °C | 54.86 mm |
| February | 16.1 °C | 25.7 °C | 56.39 mm |
| March | 17.6 °C | 26.8 °C | 66.55 mm |
| April | 19.8 °C | 28.7 °C | 82.04 mm |
| May | 22.1 °C | 30.3 °C | 153.42 mm |
| June | 23.9 °C | 31.7 °C | 250.44 mm |
| July | 24.6 °C | 32.4 °C | 198.12 mm |
| August | 24.7 °C | 32.6 °C | 229.11 mm |
| September | 24.3 °C | 31.7 °C | 244.35 mm |
| October | 22.6 °C | 30.1 °C | 199.9 mm |
| November | 19.2 °C | 27.3 °C | 78.23 mm |
| December | 16.8 °C | 25.6 °C | 65.79 mm |
| Annual | 20.6 °C | 29 °C | 1679.2 mm |
| Average First Frost Date | No Frost |
| Average Last Frost Date | |
| Average Days With Frost | Frost Free |
| Plant Hardiness Zone | Zone 11a : 4.4°C to 7.2°C |
| Plant Hardiness Zone - 2012 | Zone 10b : 1.7°C to 4.4°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Am - Tropical Monsoon |