September weather forecast
South Beach, FL

September, the first month of the autumn in South Beach, is also a moderately hot month, with an average temperature ranging between min 77.4°F (25.2°C) and max 85.5°F (29.7°C).

Temperature

The introduction of September notes a subtle temperature variation to a moderately hot 85.5°F (29.7°C) from August's 87.4°F (30.8°C). In South Beach, the nightly September temperatures experience a slight descent from daily highs to an average low of 77.4°F (25.2°C).

Heat index

For most parts of September, the heat index is estimated at a fiery hot 96.8°F (36°C). Incorporate additional safety actions, heat cramps and heat exhaustion are possible. Long-term activity may induce heatstroke.
Remember that heat index calculations are made for conditions in the shade with light wind. Exposure to the sun directly might heighten the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'felt air temperature', marries air temperature and humidity to produce a value illustrating perceived warmth. Elements such as metabolic variations, being pregnant, and physical activity can impact one's weather perception. Do note, being directly under sun rays can amplify the heat you feel, potentially raising the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. Young ones often ignore the need to take a break and drink fluids. Thirst is a late-stage symptom of dehydration - hence, maintaining hydration, particularly during extended physical activities, is crucial.
Perspiration, which is the evaporation of sweat, is a primary way the human body manages and dispels excessive warmth. When the air holds a significant amount of moisture, the efficiency of the evaporation process is decreased, preventing the body from cooling down efficiently, leading to the sensation of overheating. When heat gain exceeds the level the body can remove, body temperature begins to rise, and heat-related illnesses and disorders may develop.

Humidity

In September, the average relative humidity is 78%.

Rainfall

In September, the rain falls for 19.6 days. Throughout September, 1.26" (32mm) of precipitation is accumulated. Throughout the year, there are 153.2 rainfall days, and 13.15" (334mm) of precipitation is accumulated.

Ocean temperature

In September, the average ocean temperature is 84°F (28.9°C).
Note: Temperatures between 77°F (25°C) and 84.2°F (29°C) are excellent for swimming, diving, and other water activities, providing comfort and enjoyment for extended periods without discomfort.

Daylight

The average length of the day in September in South Beach is 12h and 19min.
On the first day of September, sunrise is at 7:00 am and sunset at 7:41 pm. On the last day of the month, sunrise is at 7:13 am and sunset at 7:08 pm EDT.

Sunshine

In South Beach, the average sunshine in September is 9h.

UV index

May through September, with an average maximum UV index of 7, are months with the highest UV index. A UV Index value of 6 to 7 symbolizes a high threat to health from unsafe exposure to UV radiation for the average person.
Note: In September, the maximum UV index of 7 translates into these guidelines:
Resist extreme sun exposure. Guarding against solar damage is essential. Try to minimize direct Sun exposure between 10 a.m. and 4 p.m., the peak period for UV radiation. Also note that objects like parasols or canopies might not provide complete sun protection. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage. Warning! Sand and water reflections boost the intensity of UV exposure.