Climate Overview
The climate in Key Largo is hot. The average annual temperature is 25°C and approximately 1072mm of precipitation falls per year. August is the wettest month, receiving around 167mm of rainfall. Key Largo is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: July, August, June. The coldest months are February, January, November, when temperatures can drop to 18°C.
Temperature
Key Largo sees moderate temperature variation throughout the year, ranging from 18°C to 30°C. The warmest month is July, when average highs reach 30°C and the mean temperature sits around 29°C. February is the coolest month, with minimum temperatures around 18°C and an average of 20°C. Daily temperature variation is modest, with an average difference of 3°C between highs and lows. The sharpest temperature change occurs between February and March, with a 3°C shift in average temperatures.
Precipitation
Key Largo is a moderately rainy area, receiving approximately 1072mm of precipitation annually, which averages out to around 89mm per month. The wettest month is August, averaging 167mm of rainfall. September and January also tend to see above-average precipitation. The driest month is November, with just 21mm. That's 147mm less than August, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic.
Wind
Key Largo is relatively calm, with an average annual wind speed of 4km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is October, averaging 6km/h, though still comfortable for most outdoor activities. The calmest conditions occur in September, with average winds dropping to 3km/h, making it an ideal period for wind-sensitive activities. Wind speeds vary significantly across the year, with a 3km/h difference between the calmest and windiest months. This level of variation is worth factoring into travel plans.
Seasons
53 days until Autumn
It is currently summer in Key Largo, which began on June 21, 2026. Key Largo is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in July at around 30°C, while the coldest stretch bottoms out in February near 18°C. Autumn is next, beginning on September 23, 2026 — 53 days from now.
Spring
Temperatures range from 22 to 28°C. Precipitation is moderate at around 185mm for the season, averaging 62mm per month. Winds are generally light, averaging 4km/h. Light layers work well as temperatures warm through the season — a great time to be outdoors.
Summer
Temperatures range from 27 to 30°C. Rainfall is heavy, totalling around 393mm across the season with a monthly average of 131mm. Winds are generally light, averaging 4km/h. Light, breathable clothing is ideal — perfect conditions for outdoor activities.
Autumn
Temperatures range from 22 to 29°C. Precipitation is moderate at around 284mm for the season, averaging 95mm per month. Winds are generally light, averaging 4km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from 18 to 26°C. Precipitation is moderate at around 210mm for the season, averaging 70mm per month. Winds are generally light, averaging 5km/h. A light jacket or sweater is usually sufficient, though cooler evenings may call for an extra layer.
Best Time to Visit
The best time to visit Key Largo is during February, March, April, November and December, when the weather is most comfortable for travellers. During these months, average temperatures hover around 23°C with modest rainfall averaging 30mm per month. By contrast, July can be uncomfortably hot with temperatures reaching 30°C. A light rain jacket is recommended, though showers are generally brief and shouldn't disrupt your plans.
Monthly Climate Data
The table below shows monthly climate averages for Key Largo based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.
