September weather forecastBelleair Beach, FL
September
Weather in September
The first month of the autumn, September, is still a tropical month in Belleair Beach, Florida, with an average temperature ranging between max 86.2°F (30.1°C) and min 77.9°F (25.5°C).Temperature
With the onset of September, the average high-temperature registers at a still hot 86.2°F (30.1°C), subtly different from August's 87.6°F (30.9°C). An average nighttime temperature of 77.9°F (25.5°C) marks September.Heat index
In September, the heat index is evaluated at a very hot 96.8°F (36°C). Adopt enhanced safety measures, heat exhaustion and heat cramps could occur. Continuous activity may induce heatstroke.Consider that heat index readings are for situations in the shade and light wind. Heat index values may surge by up to 15 Fahrenheit (8 Celsius) degrees in the presence of direct sunlight.
Note: The heat index, also known as 'feels like' or 'real feel', is a fusion of air temperature and moisture levels to demonstrate the sensation of heat. Additional factors encompassing metabolic differences, the level of physical activity, and clothing can impact the individual's perception of temperature. Direct sun rays can make one feel hotter, potentially raising the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical to babies and toddlers. Children frequently underestimate the importance of resting and drinking fluids. Thirst is a symptom of advanced dehydration - hence the need to hydrate regularly, especially during protracted physical exercises.
In the face of high temperatures, the human body's reflex is to perspire, leveraging sweat evaporation for cooling. When the relative humidity is high, the evaporation rate is reduced. The warmth is removed from the body at a lower rate, causing the body to retain more heat than it would in dry air. The body is at risk of dehydration and related complications when it fails to shed excessive heat.
Humidity
The average relative humidity in September is 74%.Rainfall
In September, the rain falls for 20.7 days. Throughout September, 2.17" (55mm) of precipitation is accumulated. Throughout the year, there are 149.9 rainfall days, and 16.18" (411mm) of precipitation is accumulated.Ocean temperature
In Belleair Beach, the average seawater temperature in September is 84.7°F (29.3°C).Note: Temperatures between 77°F (25°C) and 84.2°F (29°C) in water are ideal for swimming, diving, and other activities, providing enjoyment and comfort for extended durations.
Daylight
In September, the average length of the day is 12h and 19min.On the first day of September, sunrise is at 7:10 am and sunset at 7:51 pm. On the last day of the month, sunrise is at 7:24 am and sunset at 7:18 pm EDT.
Sunshine
In September, the average sunshine is 9.1h.UV index
May through September, with an average maximum UV index of 7, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high health vulnerability from exposure to the Sun's UV rays for the ordinary person.Note: The UV index of 7 in September translates into these instructions:
Take precautions and adopt sun safety practices. Protection against sunburn is obliged. Stay in the shade and avoid direct Sun exposure from 10 a.m. to 4 p.m., a time when UV radiation is at its strongest, and remember that parasols or canopies do not offer full protection. It's wise to wear UVA and UVB-blocking sunglasses when the sun shines brightly. Notice! The Sun's UV exposure elevates with sand and water reflections.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Belleair Beach, FL
- Average high temperature in September: 86.2°F
The warmest month (with the highest average high temperature) is August (87.6°F).
The month with the lowest average high temperature is January (65.8°F).
- Average low temperature in September: 77.9°F
The month with the highest average low temperature is August (80.6°F).
The coldest month (with the lowest average low temperature) is January (55.9°F).
Average pressure in September
Belleair Beach, FL
- Average pressure in September: 29.96"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is September (29.96"Hg).
Average wind speed in September
Belleair Beach, FL
- Average wind speed in September: 8mph
The windiest months (with the highest average wind speed) are January and March (9.8mph).
The calmest month (with the lowest average wind speed) is July (7.1mph).
Average humidity in September
Belleair Beach, FL
- Average humidity in September: 74%
The month with the highest relative humidity is December (77%).
The month with the lowest relative humidity is October (72%).
Average rainfall in September
Belleair Beach, FL
- Average rainfall in September: 2.17"
The wettest month (with the highest rainfall) is August (3.07").
The driest month (with the least rainfall) is March (0.39").
Average rainfall days in September
Belleair Beach, FL
- Average rainfall days in September: 20.7 days
The month with the highest number of rainy days is August (22.7 days).
The month with the least rainy days is February (6.7 days).
Average sea temperature in September
Belleair Beach, FL
- Average sea temperature in September: 84.7°F
The best month for swimming (with the highest average sea temperature) is August (86.7°F).
The coldest month (with the lowest average sea temperature) is January (64°F).
Average daylight in September /
Average sunshine in September
Belleair Beach, FL
- Average daylight in September: 12h and 18min
The month with the longest days is June (Average daylight: 13h and 54min).
The month with the shortest days is December (Average daylight: 10h and 24min).
- Average sunshine in September: 9h and 6min
The month with the most sunshine is May (Average sunshine: 11h and 18min).
The month with the least sunshine is December (Average sunshine: 6h and 30min).
Average sunshine days in September
Belleair Beach, FL
- Average sunshine days in September: 5.5 days
The month with the most sunshine days is January (22.8 days).
The month with the least sunshine days is August (5 days).
Average UV index in September
Belleair Beach, FL
- Average UV index in September: 7
The months with the highest UV index are May, June, July, August and September (UV index 7).
The month with the lowest UV index is January (UV index 4).
Average cloud cover in September
Belleair Beach, FL
- Average cloud cover in September: 26
The months with the most cloud cover are January and December (Cloud cover 30).
The month with the least cloud cover is May (Cloud cover 20).
Average visibility in September
Belleair Beach, FL
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).





