September weather forecastDuck Key, FL
September
Weather in September
The first month of the autumn, September, is still a warm month in Duck Key, Florida, with an average temperature varying between 84.6°F (29.2°C) and 82°F (27.8°C).Temperature
The onset of September notes an average high-temperature of a still warm 84.6°F (29.2°C), subtly shifted from August's 85.5°F (29.7°C). Throughout September, Duck Key records a steady low-temperature average of 82°F (27.8°C), a minor decrease from its daytime counterpart.Heat index
The heat index value for September is appraised at a tropical 93.2°F (34°C). Extra safeguards are necessary to prevent heat exhaustion and heat cramps. Prolonged activity might cause heatstroke.Consider that heat index readings are for situations in the shade and light wind. Uninterrupted exposure to the sun may boost the heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'apparent temperature', reflects the blend of air temperature and relative humidity to give a temperature impression. The individual's experience of temperature can be shaped by numerous aspects such as metabolic variations, physical exertion, and attire. Direct sunlight exposure should be noted as it has the potential to increase the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical to babies and toddlers. Young ones regularly neglect the requirement for rest and fluid replenishment. Thirst is a late stage of dehydration - so, it is necessary to keep hydrated, particularly during extended periods of physical exertion.
Humidity
In Duck Key, the average relative humidity in September is 74%.Rainfall
The month with the most rainfall is September, when the rain falls for 23 days and typically aggregates up to 4.21" (107mm) of precipitation.Ocean temperature
In September, the average ocean temperature is 85.5°F (29.7°C).Note: Surface water temperatures ranging from 77°F (25°C) to 84.2°F (29°C) are considered superb and highly pleasant for water activities over extended periods.
Daylight
In September, the average length of the day is 12h and 17min.On the first day of the month, sunrise is at 7:04 am and sunset at 7:41 pm. On the last day of September, sunrise is at 7:15 am and sunset at 7:11 pm EDT.
Sunshine
In September, the average sunshine is 9h.UV index
April through October, 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 health risk from unprotected exposure to Sun's UV rays for the average person.Note: A daily maximum UV index of 7 in September translates into the following instructions:
Avert overexposure. Light-skinned people might experience burning in less than 20 minutes. Seek shade and minimize exposure to direct Sun in a period between 10 a.m. and 4 p.m. when UV radiation is most intense; keep in mind that shade structures like parasols or canopies do not provide perfect sun protection. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck. Be on guard! The reflective nature of sand and water boosts UV exposure.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Duck Key, FL
- Average high temperature in September: 84.6°F
The warmest month (with the highest average high temperature) is August (85.5°F).
The month with the lowest average high temperature is January (72.9°F).
- Average low temperature in September: 82°F
The month with the highest average low temperature is August (82.9°F).
The coldest month (with the lowest average low temperature) is January (67.5°F).
Average pressure in September
Duck Key, FL
- Average pressure in September: 29.94"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The months with the lowest atmospheric pressure are September and October (29.94"Hg).
Average wind speed in September
Duck Key, FL
- Average wind speed in September: 9.8mph
The windiest month (with the highest average wind speed) is January (13.4mph).
The calmest month (with the lowest average wind speed) is July (9mph).
Average humidity in September
Duck Key, FL
- Average humidity in September: 74%
The months with the highest relative humidity are February and December (77%).
The month with the lowest relative humidity is March (73%).
Average rainfall in September
Duck Key, FL
- Average rainfall in September: 4.21"
The wettest month (with the highest rainfall) is September (4.21").
The driest month (with the least rainfall) is March (0.43").
Average rainfall days in September
Duck Key, FL
- Average rainfall days in September: 23 days
The month with the highest number of rainy days is September (23 days).
The month with the least rainy days is February (10.3 days).
Average sea temperature in September
Duck Key, FL
- Average sea temperature in September: 85.4°F
The best month for swimming (with the highest average sea temperature) is August (86.6°F).
The coldest months (with the lowest average sea temperature) are January and February (73.9°F).
Average daylight in September /
Average sunshine in September
Duck Key, FL
- Average daylight in September: 12h and 18min
The month with the longest days is June (Average daylight: 13h and 42min).
The month with the shortest days is December (Average daylight: 10h and 36min).
- Average sunshine in September: 9h and 0min
The month with the most sunshine is July (Average sunshine: 11h and 6min).
The month with the least sunshine is December (Average sunshine: 6h and 36min).
Average sunshine days in September
Duck Key, FL
- Average sunshine days in September: 4.6 days
The month with the most sunshine days is March (18 days).
The month with the least sunshine days is September (4.6 days).
Average UV index in September
Duck Key, FL
- Average UV index in September: 7
The months with the highest UV index are April, May, June, July, August, September and October (UV index 7).
The month with the lowest UV index is January (UV index 5).
Average cloud cover in September
Duck Key, FL
- Average cloud cover in September: 28
The months with the most cloud cover are January and October (Cloud cover 32).
The month with the least cloud cover is April (Cloud cover 23).
Average visibility in September
Duck Key, 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).
