September weather forecastSumner, FL
September
Weather in September
September, the first month of the autumn in Sumner, is still a tropical month, with an average temperature ranging between min 72.9°F (22.7°C) and max 87.3°F (30.7°C).Temperature
September's arrival brings an average high-temperature of a still hot 87.3°F (30.7°C), slightly deviating from August's 90.3°F (32.4°C). Nighttime temperatures hover around an average low of 72.9°F (22.7°C) in September.Heat index
The heat index value during September is estimated at a very hot 102.2°F (39°C). Take greater precautions, heat exhaustion and heat cramps may be expected. Heatstroke could result from lengthy activity.Thinking about the heat index, one should account for its values in shaded areas with gentle breezes. Direct sunlight exposure may result in a rise of the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', takes into account both air temperature and humidity to illustrate what people actually feel. An individual's perception of weather can be affected by a variety of elements including metabolic differences, being pregnant, and their level of physical exertion. Sunshine, when direct, has the potential to intensify weather effects, leading to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values remain especially vital 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 innate cooling system of the human body revolves around perspiration, with the evaporation of sweat being central to this process. In the presence of abundant moisture in the atmosphere, the cooling process through evaporation is hindered, causing the body to feel excessively warm. As body temperatures escalate without effective heat release, one might face dehydration threats.
Humidity
September is the most humid month, with an average relative humidity of 77%.Rainfall
In Sumner, in September, it is raining for 18.7 days, with typically 1.85" (47mm) of accumulated precipitation. Throughout the year, there are 154 rainfall days, and 21.69" (551mm) of precipitation is accumulated.Snowfall
January through November are months without snowfall.Daylight
The average length of the day in September is 12h and 20min.On the first day of the month, sunrise is at 7:09 am and sunset at 7:53 pm. On the last day of September, sunrise is at 7:24 am and sunset at 7:18 pm EDT.
Sunshine
In Sumner, the average sunshine in September is 8.6h.UV index
The average daily maximum UV index in September in Sumner is 6. A UV Index of 6 to 7 symbolizes a high health risk from unsafe exposure to UV radiation for the average person.Note: The maximum daily UV index of 6 during September translates into the following directions:
Exercise precautions and adapt sun safety practices. Defence against skin and eye affliction is paramount. Limit your exposure to the sun's UV radiation, which is strongest between 10 a.m. and 4 p.m., and note that parasols or canopies may not provide full sun protection. For a sun-safe wardrobe, go for clothes that are tightly woven and generously sized.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Sumner, FL
- Average high temperature in September: 87.3°F
The warmest month (with the highest average high temperature) is August (90.3°F).
The month with the lowest average high temperature is January (64°F).
- Average low temperature in September: 72.9°F
The month with the highest average low temperature is August (76.5°F).
The coldest month (with the lowest average low temperature) is January (47.7°F).
Average pressure in September
Sumner, FL
- Average pressure in September: 29.97"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is September (29.97"Hg).
Average wind speed in September
Sumner, FL
- Average wind speed in September: 5.4mph
The windiest months (with the highest average wind speed) are January, February and March (7.3mph).
The calmest months (with the lowest average wind speed) are July and August (5.2mph).
Average humidity in September
Sumner, FL
- Average humidity in September: 77%
The month with the highest relative humidity is September (77%).
The month with the lowest relative humidity is January (71%).
Average rainfall in September
Sumner, FL
- Average rainfall in September: 1.85"
The wettest month (with the highest rainfall) is August (3.58").
The driest month (with the least rainfall) is November (0.83").
Average rainfall days in September
Sumner, FL
- Average rainfall days in September: 18.7 days
The month with the highest number of rainy days is July (22.8 days).
The month with the least rainy days is November (6.6 days).
Average snowfall days in September
Sumner, FL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is December (0.1 days).
The months with the least snowfall days are January, February, March, April, May, June, July, August, September, October and November (0 days).
Average daylight in September /
Average sunshine in September
Sumner, FL
- Average daylight in September: 12h and 18min
The month with the longest days is June (Average daylight: 14h and 0min).
The month with the shortest days is December (Average daylight: 10h and 18min).
- Average sunshine in September: 8h and 36min
The month with the most sunshine is July (Average sunshine: 10h and 48min).
The month with the least sunshine is December (Average sunshine: 6h and 0min).
Average sunshine days in September
Sumner, FL
- Average sunshine days in September: 8.8 days
The month with the most sunshine days is November (22.3 days).
The month with the least sunshine days is July (5.8 days).
Average UV index in September
Sumner, FL
- Average UV index in September: 6
The months with the highest UV index are May, June, July and August (UV index 7).
The months with the lowest UV index are January and December (UV index 4).
Average cloud cover in September
Sumner, FL
- Average cloud cover in September: 31
The months with the most cloud cover are February and December (Cloud cover 36).
The month with the least cloud cover is May (Cloud cover 25).
Average visibility in September
Sumner, 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).





