Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
September brings an average high-temperature of a still warm 84.6°F (29.2°C), showing a slight difference from August's 85.5°F (29.7°C). A mean low-temperature of 82°F (27.8°C) is anticipated during the month of September, a slight step down from the daytime high.Heat index
September's average heat index is appraised at a tropical 93.2°F (34°C). Heightened safety actions are necessary, heat cramps and heat exhaustion are probable. Persistent activity may lead to heatstroke.The metrics for the heat index are tailored for both shady environments and light winds. The heat index could experience an increase of 15 Fahrenheit (8 Celsius) degrees due to direct sunlight.
Note: The heat index, also known as 'apparent temperature' or 'feels like', shows a temperature sensation when both heat and moisture conditions are combined. This effect is personal, influenced by the individual's physical activity and heat sensitivity, shaped by factors including wind, attire, and metabolic variations. Being under direct sunshine can magnify the heat experience, possibly pushing up the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for children. Younglings are generally more in peril than adults due to their reduced perspiration. Coupled with a larger skin surface relative to their tiny bodies and greater heat production because of their activity, they become more at risk.
Humidity
In September, the average relative humidity 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.Daylight
The average length of the day in September is 12h and 17min.On the first day of September, sunrise is at 7:06 am and sunset at 7:43 pm. On the last day of the month, sunrise is at 7:17 am and sunset at 7:13 pm EDT.
Sunshine
In Big Pine Key, Florida, the average sunshine in September 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 estimate of 6 to 7 represents a high threat to health from exposure to the Sun's UV rays for average individuals.Note: During September, 7 as the daily maximum UV index converts into the following advice:
Avoid excessive sunlight. Those with lighter skin may 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.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot does it get in September?
What is the average humidity in September?
What is the rainiest month?
How many days does it rain in September?
How many hours of daylight does Big Pine Key have in September?
What time are sunrise and sunset in September?
How many hours of sunshine does Big Pine Key have in September?
When is the highest UV index?
How high is the UV index in September?
Average temperature in September
Big Pine 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
Big Pine 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
Big Pine 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
Big Pine 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
Big Pine 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
Big Pine 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 daylight in September /
Average sunshine in September
Big Pine Key, FL
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 13h and 36min).
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
Big Pine 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
Big Pine 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
Big Pine 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
Big Pine 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).
Big Pine Key, Florida, USA
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