Casselberry, Florida has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 62.3 °F (low) to 82.4 °F (high). Annual precipitation averages 56.2 Inches. Casselberry is located in USDA Plant Hardiness Zone 10a.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 48.3 °F | 70.4 °F | 2.96 in. |
| February | 50.8 °F | 73.2 °F | 2.49 in. |
| March | 54.8 °F | 77.6 °F | 3.51 in. |
| April | 60.3 °F | 82.7 °F | 3.07 in. |
| May | 66.5 °F | 87.6 °F | 3.86 in. |
| June | 72.0 °F | 90.4 °F | 8.25 in. |
| July | 73.8 °F | 91.8 °F | 7.61 in. |
| August | 74.1 °F | 91.6 °F | 8.25 in. |
| September | 72.5 °F | 89.2 °F | 7.35 in. |
| October | 66.0 °F | 84.2 °F | 4.02 in. |
| November | 57.4 °F | 77.4 °F | 2.26 in. |
| December | 51.6 °F | 72.7 °F | 2.59 in. |
| Annual | 62.3 °F | 82.4 °F | 56.22 in. |
| Average First Frost Date | Frost Rare |
| Average Last Frost Date | |
| Average Days With Frost | Frost Rare |
| Plant Hardiness Zone | Zone 10a : 30°F to 25°F |
| Plant Hardiness Zone - 2012 | Zone 9b : 25°F to 20°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |