September weather forecast
Miami, FL

In September, Miami, Florida experiences a gradual decline in temperature marking the end of the sweltering summer season. The saturated air, attaining the year's highest humidity of 73%, is a significant feature this month. Compared to the preceding month, September is cooler yet maintains a similar pattern of afternoon thunderstorms. The city starts to witness a decrease in temperature and humidity, providing a respite from the peak summer conditions. Moving into October, residents can expect the onset of drier and more pleasant weather conditions.

Temperature

As Miami transitions into September, the average high-temperature stands at a warm 85.6°F, offering little variation from the preceding month. Miami encounters a small divergence from daytime high temperatures, averaging a low-temperature of 81°F during September nights.

Heat index

In September, the heat index is calculated to be a torrid 95°F. Adopt enhanced safety measures, heat exhaustion and heat cramps could occur. Continuous activity may induce heatstroke.
When considering the heat index, it's pivotal to note it is for shade and mild wind conditions. Exposure to direct sunshine can increase heat index values by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'feels like', reflects the blend of air temperature and relative humidity to give a temperature impression. Physical activity, clothing, and metabolic variations are additional factors that impact an individual's perception of temperature. Being under direct sunshine can magnify the heat experience, possibly pushing up the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely vital to babies and toddlers. Typically, young kids are at a higher risk than adults since they sweat less. Also, the larger skin surface in proportion to their small bodies and the heightened heat production due to their active nature adds to their vulnerability.
To prevent overheating and help regulate its internal temperature, the human body sweat and rely on the evaporation to cool down. Under high air temperature and high humidity (high heat index) conditions, the body's ability to perspire is compromised, increasing the sensation of heat. The body is at risk of dehydration and related complications when it fails to shed excessive heat.

Humidity

In Miami, the average relative humidity in September is 73%.

Rainfall

In Miami, during September, the rain falls for 24.5 days and regularly aggregates up to 1.93" of precipitation. Throughout the year, in Miami, there are 182.7 rainfall days, and 16.38" of precipitation is accumulated.

Ocean temperature

In Miami, the average seawater temperature in September is 85.5°F.
Note: Water temperatures from 77°F to 84.2°F make swimming, diving, and similar activities highly pleasurable and enjoyable for long periods without discomfort.

Daylight

The average length of the day in September in Miami, Florida, is 12h and 17min.
On the first day of the month, sunrise is at 7:01 am and sunset at 7:40 pm. On the last day of September, in Miami, sunrise is at 7:12 am and sunset at 7:08 pm EDT.

Sunshine

In Miami, Florida, the average sunshine in September is 9.1h.

UV index

The months with the highest UV index are May through October, with an average maximum UV index of 7. A UV Index reading of 6 to 7 represents a high health vulnerability from exposure to the Sun's UV radiation for ordinary individuals.
Note: In September, an average UV index of 7 transforms into the following instructions:
Avert overexposure. Light-skinned people might experience burning in less than 20 minutes. Avoid direct exposure to the Sun between 10 a.m. and 4 p.m., the peak period for UV radiation, noting that objects like parasols or canopies might not offer complete sun protection. Protect your eyes, ears, face, and neck from the Sun by wearing a wide-brimmed hat. Caution! The Sun's UV rays become stronger due to reflections from water and sand.