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 snowfall in September
- Average snowfall 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
The arrival of September marks a slight shift to an average high-temperature of a moderately hot 83.3°F (28.5°C) from August's 87.1°F (30.6°C). In Hilton Head Island, an average low-temperature of 74.1°F (23.4°C) is recorded during September nights.Heat index
September's heat index is appraised at a tropical 89.6°F (32°C). Constant activity during exposure could result in a state of weariness and possibly heat cramps.The heat index's values are generally associated with conditions in shade and light breezes. A rise in the heat index by 15 Fahrenheit (8 Celsius) degrees may result from direct sunlight exposure.
Note: The heat index, also known as 'apparent temperature' or 'feels like', shows a temperature sensation when both heat and moisture conditions are combined. An individual's perception of weather can be influenced by a variety of factors including metabolic differences, being pregnant, and their degree of physical exertion. Keep in mind that direct sunshine exposure can amplify the weather's effects, possibly increasing the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely vital to babies and toddlers. Young individuals are typically more threatened than adults due to their reduced perspiration. Also, the larger skin surface proportionate to their small bodies and the increased heat from their activities magnify their risk.
Humidity
In Hilton Head Island, the average relative humidity in September is 75%.Rainfall
In Hilton Head Island, in September, it is raining for 17.9 days, with typically 3.78" (96mm) of accumulated precipitation. In Hilton Head Island, during the entire year, the rain falls for 175.3 days and collects up to 32.28" (820mm) of precipitation.Snowfall
February through December are months without snowfall in Hilton Head Island.Ocean temperature
In Hilton Head Island, South Carolina, in September, the average water temperature is 81.7°F (27.6°C).Note: Temperatures between 77°F (25°C) and 84.2°F (29°C) in water are ideal for swimming, diving, and other activities, providing enjoyment and comfort for extended durations.
Daylight
In Hilton Head Island, South Carolina, the average length of the day in September is 12h and 21min.On the first day of the month, sunrise is at 6:58 am and sunset at 7:46 pm. On the last day of September, sunrise is at 7:16 am and sunset at 7:08 pm EDT.
Sunshine
The average sunshine in September is 8.8h.UV index
In September, the average daily maximum UV index in Hilton Head Island, South Carolina, is 6. A UV Index estimate of 6 to 7 represents a high health risk from unsafe exposure to UV radiation for average individuals.Note: A maximum UV index of 6 in September translates into the following recommendations:
Prevent overexposure. Protection from the sun's harmful effects is needed. From 10 a.m. to 4 p.m., when UV radiation is at its strongest, limit direct exposure to the Sun and note that shade structures may not provide full sun protection. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection. Caution! The Sun's UV intensity grows with reflections off sand and water.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot is September in Hilton Head Island?
What is the average humidity in September in Hilton Head Island?
How much does it rain in Hilton Head Island in September?
When it does not snow in Hilton Head Island?
What is the ocean temperature in September in Hilton Head Island?
What is the average length of the day in September in Hilton Head Island?
What time are sunrise and sunset in September in Hilton Head Island?
How long on average sun shines in September in Hilton Head Island?
How high is the UV index in September in Hilton Head Island?
Average temperature in September
Hilton Head Island, SC
- Average high temperature in September: 83.3°F
The warmest month (with the highest average high temperature) is July (87.6°F).
The month with the lowest average high temperature is January (57.4°F).
- Average low temperature in September: 74.1°F
The month with the highest average low temperature is July (77.9°F).
The coldest month (with the lowest average low temperature) is January (46°F).
Average pressure in September
Hilton Head Island, SC
- Average pressure in September: 29.99"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The months with the lowest atmospheric pressure are June and August (29.98"Hg).
Average wind speed in September
Hilton Head Island, SC
- Average wind speed in September: 8.5mph
The windiest months (with the highest average wind speed) are January, March and April (9.6mph).
The calmest month (with the lowest average wind speed) is August (7.8mph).
Average humidity in September
Hilton Head Island, SC
- Average humidity in September: 75%
The month with the highest relative humidity is December (77%).
The month with the lowest relative humidity is January (72%).
Average rainfall in September
Hilton Head Island, SC
- Average rainfall in September: 3.78"
The wettest month (with the highest rainfall) is August (6.06").
The driest month (with the least rainfall) is January (1.02").
Average rainfall days in September
Hilton Head Island, SC
- Average rainfall days in September: 17.9 days
The month with the highest number of rainy days is August (25 days).
The month with the least rainy days is January (8.3 days).
Average snowfall in September
Hilton Head Island, SC
- Average snowfall in September: 0"
The month with the highest snowfall is January (0.04").
The months with the least snowfall are February, March, April, May, June, July, August, September, October, November and December (0").
Average snowfall days in September
Hilton Head Island, SC
- Average snowfall days in September: 0 days
The months with the highest number of snowfall days are January and February (0.1 days).
The months with the least snowfall days are March, April, May, June, July, August, September, October, November and December (0 days).
Average sea temperature in September
Hilton Head Island, SC
- Average sea temperature in September: 81.8°F
The best month for swimming (with the highest average sea temperature) is August (83.5°F).
The coldest month (with the lowest average sea temperature) is February (57.5°F).
Average daylight in September /
Average sunshine in September
Hilton Head Island, SC
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 12min).
The month with the shortest days is December (Average daylight: 10h and 6min).
- Average sunshine in September: 8h and 5min
The months with the most sunshine are June and July (Average sunshine: 11h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 42min).
Average sunshine days in September
Hilton Head Island, SC
- Average sunshine days in September: 8.3 days
The month with the most sunshine days is January (20.3 days).
The month with the least sunshine days is August (2.8 days).
Average UV index in September
Hilton Head Island, SC
- Average UV index in September: 6
The months with the highest UV index are May, June, July and August (UV index 7).
The month with the lowest UV index is January (UV index 3).
Average cloud cover in September
Hilton Head Island, SC
- Average cloud cover in September: 28
The months with the most cloud cover are February and December (Cloud cover 38).
The months with the least cloud cover are June and July (Cloud cover 25).
Average visibility in September
Hilton Head Island, SC
- 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).
Hilton Head Island, South Carolina, USA
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