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 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
With September's onset, the weather reveals a slight temperature decrease, transitioning from a hot 89.2°F (31.8°C) in August to a moderately hot 83.7°F (28.7°C). Duncan experiences a consistent average temperature of 62.8°F (17.1°C) throughout the nights in September.Heat index
Throughout September, the heat index is evaluated at a tropical 89.6°F (32°C). If one persists in activity during exposure, it could induce weariness and subsequently, heat cramps.It is crucial to understand that heat index figures are for shade and gentle wind conditions. Exposure to direct sunshine can increase heat index values by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'felt air temperature', stands as a testimony to how temperature and humidity combine to impact our sense of warmth. The influence of weather is personal, differing among a variety of individuals based on differences in body mass, stature, and the level of physical activity. 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 particularly meaningful for babies and toddlers. Kids are usually in more danger than grown-ups as they tend to sweat less. Plus, their bigger skin surface in relation to their small frames and increased heat generation due to their activity level make them more susceptible.
Humidity
In Duncan, the average relative humidity in September is 71%.Rainfall
The month with the least rainfall is September, when the rain falls for 11.2 days and typically collects 1.38" (35mm) of precipitation.Snowfall
April through October are months without snowfall.Daylight
In September, the average length of the day in Duncan is 12h and 23min.On the first day of the month, sunrise is at 7:01 am and sunset at 7:54 pm. On the last day of September, in Duncan, sunrise is at 7:23 am and sunset at 7:13 pm EDT.
Sunshine
The average sunshine in September is 8.4h.UV index
In September, the average daily maximum UV index in Duncan is 5. A UV Index value of 3 to 5 symbolizes a medium vulnerability from unsafe exposure to UV radiation for ordinary individuals.Note: A maximum high daily UV index of 5 during September translates into the following directions:
Stay alert. Light-skinned people could suffer burns in less than 30 minutes. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. For minimizing sun-related eye damage, always choose sunglasses with UVA and UVB coverage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot does it get in Duncan in September?
What is the average humidity in September in Duncan?
What is the driest month in Duncan?
How much does it rain in Duncan in September?
When it does not snow in Duncan?
How many hours of daylight does Duncan have in September?
When are sunrise and sunset in September in Duncan?
How long on average sun shines in September in Duncan?
What is the UV index reading in September in Duncan?
Average temperature in September
Duncan, SC
- Average high temperature in September: 83.7°F
The warmest month (with the highest average high temperature) is July (91°F).
The month with the lowest average high temperature is January (48.9°F).
- Average low temperature in September: 62.8°F
The month with the highest average low temperature is July (69.1°F).
The coldest month (with the lowest average low temperature) is January (32.9°F).
Average pressure in September
Duncan, SC
- Average pressure in September: 30.04"Hg
The month with the highest atmospheric pressure is November (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.99"Hg).
Average wind speed in September
Duncan, SC
- Average wind speed in September: 5mph
The windiest month (with the highest average wind speed) is April (7mph).
The calmest month (with the lowest average wind speed) is August (4.3mph).
Average humidity in September
Duncan, SC
- Average humidity in September: 71%
The month with the highest relative humidity is December (76%).
The month with the lowest relative humidity is July (67%).
Average rainfall in September
Duncan, SC
- Average rainfall in September: 1.38"
The wettest month (with the highest rainfall) is December (3.35").
The driest month (with the least rainfall) is September (1.38").
Average rainfall days in September
Duncan, SC
- Average rainfall days in September: 11.2 days
The month with the highest number of rainy days is July (15.3 days).
The month with the least rainy days is November (8.2 days).
Average snowfall in September
Duncan, SC
- Average snowfall in September: 0"
The month with the highest snowfall is December (2.2").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Duncan, SC
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (1.6 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Duncan, SC
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 30min).
The month with the shortest days is December (Average daylight: 9h and 54min).
- Average sunshine in September: 8h and 2min
The month with the most sunshine is July (Average sunshine: 10h and 54min).
The month with the least sunshine is December (Average sunshine: 5h and 18min).
Average sunshine days in September
Duncan, SC
- Average sunshine days in September: 17.5 days
The month with the most sunshine days is October (22.3 days).
The month with the least sunshine days is August (13.3 days).
Average UV index in September
Duncan, SC
- Average UV index in September: 5
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January and December (UV index 2).
Average cloud cover in September
Duncan, SC
- Average cloud cover in September: 32
The month with the most cloud cover is December (Cloud cover 43).
The months with the least cloud cover are June and July (Cloud cover 28).
Average visibility in September
Duncan, 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).
Duncan, South Carolina, USA
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