Key Largo, Florida has a Tropical Savanna (Wet and Dry Climate) climate (Köppen classification: Aw). Average annual temperatures range from 73 °F (low) to 82.3 °F (high). Annual precipitation averages 46.9 Inches. Key Largo is located in USDA Plant Hardiness Zone 11a.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 64.1 °F | 74.7 °F | 1.96 in. |
| February | 65.6 °F | 75.9 °F | 1.7 in. |
| March | 68.0 °F | 77.9 °F | 1.64 in. |
| April | 72.0 °F | 81.5 °F | 2.19 in. |
| May | 75.5 °F | 84.2 °F | 3.76 in. |
| June | 78.1 °F | 86.9 °F | 6.44 in. |
| July | 79.6 °F | 89.0 °F | 4.42 in. |
| August | 80.0 °F | 88.8 °F | 6.08 in. |
| September | 78.7 °F | 87.5 °F | 7.9 in. |
| October | 76.1 °F | 84.7 °F | 6.03 in. |
| November | 70.9 °F | 79.9 °F | 2.53 in. |
| December | 67.2 °F | 76.9 °F | 2.25 in. |
| Annual | 73 °F | 82.3 °F | 46.9 in. |
| Average First Frost Date | No Frost |
| Average Last Frost Date | |
| Average Days With Frost | Frost Free |
| Plant Hardiness Zone | Zone 11a : 40°F to 35°F |
| Plant Hardiness Zone - 2012 | Zone 11a : 40°F to 35°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Aw - Tropical Savanna (Wet and Dry Climate) |