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 sea temperature 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
At the start of September, Stock Island's average high-temperature reaches a still moderately hot 84.4°F (29.1°C), subtly different from the preceding month. Nights in September cool down, indicating a minor disparity from daytime highs with an average low-temperature of 82.2°F (27.9°C).Heat index
During September, the heat index is computed to be a tropical 93.2°F (34°C). Exercise heightened safety, heat cramps and heat exhaustion are probable. Persistent activity may provoke heatstroke.Note that heat index values are valued for light wind and location in the shade. Facing direct sunlight may hike up the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'real feel', is found by incorporating humidity levels into the air temperature measurement. The impact of weather is individual, with diverse individuals experiencing it differently due to variations in body mass, height, and activity levels. Awareness is key; direct sunlight can enhance the weather's impact, possibly boosting the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely vital to babies and toddlers. Young ones generally face higher dangers than adults since they sweat less. Along with their large skin surface area compared totheir small bodies and increased heat production from their activities, the risks are heightened.
Humidity
The months with the lowest humidity are July through September, with an average relative humidity of 74%.Rainfall
September is the month with the most rainfall. Rain falls for 23.1 days and accumulates 5.12" (130mm) of precipitation.Ocean temperature
In September, the average ocean temperature is 85.6°F (29.8°C).Note: Water temperature between 77°F (25°C) and 84.2°F (29°C) provides warmth and pleasure, making water activities enjoyable for lengthened periods without feeling uncomfortable.
Daylight
In Stock Island, the average length of the day in September is 12h and 17min.On the first day of September, sunrise is at 7:08 am and sunset at 7:45 pm. On the last day of the month, sunrise is at 7:18 am and sunset at 7:14 pm EDT.
Sunshine
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 in Stock Island. A UV Index value of 6 to 7 symbolizes a high health hazard from unsafe exposure to UV radiation for the average person.Note: In September, the UV index of 7 transforms into the following advice:
Fend off overexposure. Sun protection is vital. Stay out of direct sunlight between 10 a.m. and 4 p.m., when UV radiation is most intense, and remember that not all shade structures provide complete protection. For excellent sun protection for the eyes, ears, face, and neck, consider a wide-brim hat. Take note! The UV strength of the Sun elevates when reflected off water and sand.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Is it hot during September?
What is the least humid month?
What is the average humidity in September?
What is the rainiest month?
How many days does it rain in September?
How warm is the water in September in Stock Island?
What is the average length of the day in September?
What time are sunrise and sunset in September?
How many hours of sunshine does Stock Island have in September?
When is the highest UV index?
What is the UV index reading in September?
Average temperature in September
Stock Island, FL
- Average high temperature in September: 84.4°F
The warmest month (with the highest average high temperature) is August (85.3°F).
The month with the lowest average high temperature is January (72.7°F).
- Average low temperature in September: 82.2°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 (68.5°F).
Average pressure in September
Stock Island, FL
- Average pressure in September: 29.93"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The months with the lowest atmospheric pressure are September and October (29.93"Hg).
Average wind speed in September
Stock Island, FL
- Average wind speed in September: 10.3mph
The windiest months (with the highest average wind speed) are January and November (14.4mph).
The calmest month (with the lowest average wind speed) is July (9.5mph).
Average humidity in September
Stock Island, FL
- Average humidity in September: 74%
The month with the highest relative humidity is February (78%).
The months with the lowest relative humidity are July, August and September (74%).
Average rainfall in September
Stock Island, FL
- Average rainfall in September: 5.12"
The wettest month (with the highest rainfall) is September (5.12").
The driest month (with the least rainfall) is March (0.67").
Average rainfall days in September
Stock Island, FL
- Average rainfall days in September: 23.1 days
The months with the highest number of rainy days are August and September (23.1 days).
The month with the least rainy days is February (11 days).
Average sea temperature in September
Stock Island, FL
- Average sea temperature in September: 85.6°F
The best month for swimming (with the highest average sea temperature) is August (86.9°F).
The coldest months (with the lowest average sea temperature) are January and February (71.2°F).
Average daylight in September /
Average sunshine in September
Stock Island, 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 0min).
The month with the least sunshine is December (Average sunshine: 6h and 18min).
Average sunshine days in September
Stock Island, FL
- Average sunshine days in September: 4.5 days
The month with the most sunshine days is March (17 days).
The month with the least sunshine days is September (4.5 days).
Average UV index in September
Stock Island, 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
Stock Island, FL
- Average cloud cover in September: 29
The month with the most cloud cover is January (Cloud cover 34).
The month with the least cloud cover is April (Cloud cover 23).
Average visibility in September
Stock Island, 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).
Stock Island, Florida, USA
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