Climate Insights for Florida Keys Marathon International Airport

The climate in Florida Keys Marathon International Airport is hot. The average annual temperature is 26°C and approximately 887mm of precipitation falls per year. January is the wettest month, receiving around 162mm of rainfall. Florida Keys Marathon International Airport is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: August, July, September. The coldest months are February, January, March, when temperatures can drop to 20°C.

Florida Keys Marathon International Airport has relatively stable temperatures year-round, staying within a 9°C range. The warmest month is August, when average highs reach 29°C and the mean temperature sits around 29°C. February is the coolest month, with minimum temperatures around 20°C and an average of 21°C. Daily temperature variation is modest, with an average difference of 2°C between highs and lows. The sharpest temperature change occurs between February and March, with a 3°C shift in average temperatures.

Florida Keys Marathon International Airport is a moderately rainy area, receiving approximately 887mm of precipitation annually, which averages out to around 74mm per month. The wettest month is January, averaging 162mm of rainfall. August and October also tend to see above-average precipitation. The driest month is March, with just 20mm. That's 142mm less than January, 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.

Florida Keys Marathon International Airport is relatively calm, with an average annual wind speed of 6km/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 7km/h, though still comfortable for most outdoor activities. The calmest conditions occur in September, with average winds dropping to 4km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 3km/h gap between the calmest and windiest months.

It is currently summer in Florida Keys Marathon International Airport, which began on June 21, 2026. Florida Keys Marathon International Airport 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 August at around 29°C, while the coldest stretch bottoms out in February near 20°C. Autumn is next, beginning on September 23, 2026 — 52 days from now.

The best time to visit Florida Keys Marathon International Airport is during February, March, April, November and December, when the weather is most comfortable for travellers. During these months, average temperatures hover around 24°C with modest rainfall averaging 32mm per month. By contrast, August can be uncomfortably hot with temperatures reaching 29°C. A light rain jacket is recommended, though showers are generally brief and shouldn't disrupt your plans.

The table below shows monthly climate averages for Florida Keys Marathon International Airport 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.