September weather forecastDunedin, FL
September
Weather in September
September, the first month of the autumn in Dunedin, is still a hot month, with temperature in the range of an average low of 77.7°F (25.4°C) and an average high of 86.5°F (30.3°C).Temperature
With the start of September, Dunedin measures an average high-temperature of a still hot 86.5°F (30.3°C), not significantly differing from August's 88°F (31.1°C). Throughout September, a minimal difference from peak daytime temperatures is noted, marking a steady low-temperature average of 77.7°F (25.4°C).Heat index
September's mean heat index is computed to be a very hot 98.6°F (37°C). Additional precautions are required to avert heat cramps and heat exhaustion. Persistent activity may culminate in heatstroke.Take into consideration that the heat index values are calculated for shade and light wind conditions. With direct sunlight, the heat index could increase by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'felt air temperature', is a measure of how hot it feels when the actual air humidity is factored in. Elements such as metabolic variations, being pregnant, and physical activity can impact one's weather perception. In direct sunlight, the heat's impact can be heightened, potentially leading to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for babies and toddlers. Children commonly overlook the importance of rest and fluid replenishment. Thirst, being a delayed sign of dehydration, emphasizes the need to keep hydration up, especially during lengthy physical activities.
The human body keeps its cool primarily through perspiration, as this process enables sweat to evaporate, taking away the excess heat. When relative humidity increases, the body's capacity to evaporate heat decreases, leading to a heightened sense of warmth. Heat-related challenges, like dehydration, can be anticipated when body heat isn't managed effectively.
Humidity
In Dunedin, the average relative humidity in September is 74%.Rainfall
In Dunedin, in September, it is raining for 21 days, with typically 3.7" (94mm) of accumulated precipitation. Throughout the year, there are 168.5 rainfall days, and 27.4" (696mm) of precipitation is accumulated.Ocean temperature
In September, the average ocean temperature is 84.6°F (29.2°C).Note: Swimming, diving, and similar water activities in temperatures ranging from 77°F (25°C) to 84.2°F (29°C) are seen as very agreeable and pleasurable for lengthy periods without discomfort.
Daylight
In Dunedin, Florida, the average length of the day in September 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 7:23 am and sunset at 7:17 pm EDT.
Sunshine
In September, the average sunshine is 9.2h.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 unsafe exposure to UV radiation for average individuals.Note: In September, the UV index of 7 transforms into the following advice:
Take precautions against overexposure. Protection against sun damage is needed. It's important to stay in the shade and limit exposure to the sun from 10 a.m. to 4 p.m., when UV radiation is most intense, although remember that shade structures may not provide full sun protection. Sunglasses that guard against UVA and UVB rays are pivotal in minimizing sun-induced ocular damage. Attention! The combination of sand and water reflections enhances UV ray intensity.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Dunedin, FL
- Average high temperature in September: 86.5°F
The warmest month (with the highest average high temperature) is August (88°F).
The month with the lowest average high temperature is January (65.7°F).
- Average low temperature in September: 77.7°F
The month with the highest average low temperature is August (80.4°F).
The coldest month (with the lowest average low temperature) is January (55°F).
Average pressure in September
Dunedin, 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
Dunedin, FL
- Average wind speed in September: 7.6mph
The windiest months (with the highest average wind speed) are January and March (9.3mph).
The calmest month (with the lowest average wind speed) is July (6.9mph).
Average humidity in September
Dunedin, FL
- Average humidity in September: 74%
The month with the highest relative humidity is December (77%).
The months with the lowest relative humidity are May and October (72%).
Average rainfall in September
Dunedin, FL
- Average rainfall in September: 3.7"
The wettest month (with the highest rainfall) is August (5.16").
The driest month (with the least rainfall) is March (0.79").
Average rainfall days in September
Dunedin, FL
- Average rainfall days in September: 21 days
The month with the highest number of rainy days is July (25.6 days).
The month with the least rainy days is November (7.6 days).
Average sea temperature in September
Dunedin, FL
- Average sea temperature in September: 84.4°F
The best month for swimming (with the highest average sea temperature) is August (86.6°F).
The coldest month (with the lowest average sea temperature) is January (61.1°F).
Average daylight in September /
Average sunshine in September
Dunedin, 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 12min
The month with the most sunshine is May (Average sunshine: 11h and 12min).
The month with the least sunshine is December (Average sunshine: 6h and 30min).
Average sunshine days in September
Dunedin, FL
- Average sunshine days in September: 6.2 days
The month with the most sunshine days is November (21.5 days).
The month with the least sunshine days is July (3.6 days).
Average UV index in September
Dunedin, 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
Dunedin, FL
- Average cloud cover in September: 27
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
Dunedin, 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).





