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
Round O records an average high-temperature of a warm 85.6°F (29.8°C) as September arrives, nearly mirroring the previous month's climate. The low-temperature average for Round O during September stands at a pleasant 68.5°F (20.3°C).Heat index
In September, the heat index is computed to be a fiery hot 96.8°F (36°C). Exercise increased caution, heat cramps and heat exhaustion are potential hazards. Continuous activity could lead to heatstroke.Understand that the heat index values take into account shaded locations and mild winds. Exposure to the direct sun could elevate the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'feels like', is an index that combines air temperature and relative humidity to determine the human-perceived temperature equivalent. Elements of metabolic variation, physical activity, and clothing contribute to the effect of temperature on an individual. Be aware that direct exposure to sunlight increases heat impact and may raise the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are largely significant for babies and toddlers. In general, younger individuals are at greater risk than adults because they tend to sweat less. Also, having a larger skin surface to body size ratio and greater heat production due to their active behavior contribute to this danger.
The body's innate mechanism to counteract overheating is through perspiration, as it leverages the cooling effects of sweat evaporation. Increased relative humidity interferes with body cooling by slowing the rate of evaporation, resulting in a slower body cooling rate and a heightened feeling of heat. As the body gains more heat than it can dissipate, there's a risk of increasing temperatures and resultant overheating.
Humidity
In September, the average relative humidity in Round O is 76%.Rainfall
In September, the rain falls for 14.2 days. Throughout September, 1.89" (48mm) of precipitation is accumulated. Throughout the year, in Round O, there are 149.7 rainfall days, and 21.5" (546mm) of precipitation is accumulated.Snowfall
In Round O, snow does not fall in March through December.Daylight
In Round O, the average length of the day in September is 12h and 22min.On the first day of September in Round O, sunrise is at 6:57 am and sunset at 7:46 pm. On the last day of the month, sunrise is at 7:16 am and sunset at 7:07 pm EDT.
Sunshine
The average sunshine in September is 8.7h.UV index
The average daily maximum UV index in September is 6. A UV Index reading of 6 to 7 represents a high health hazard from unprotected exposure to Sun's UV rays for the ordinary person.Note: In September, the maximum UV index of 6 transforms into these recommendations:
Undertake precautions and comply with sun safety standards. Protection from skin and eye injury is vital. Between 10 a.m. and 4 p.m., UV radiation is strongest. Make an effort to avoid direct sunlight during this time, remembering that shade structures may not provide full sun protection. Tightly woven clothing, when worn loosely, shields effectively against the Sun.
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?
How much does it rain in September?
When it does not snow?
What is the average length of the day in September?
When is the sunrise / sunset in September?
How long on average sun shines in September in Round O?
How high is the UV index in September?
Average temperature in September
Round O, SC
- Average high temperature in September: 85.6°F
The warmest month (with the highest average high temperature) is July (91.8°F).
The month with the lowest average high temperature is January (56.1°F).
- Average low temperature in September: 68.5°F
The month with the highest average low temperature is July (73.4°F).
The coldest month (with the lowest average low temperature) is January (39.9°F).
Average pressure in September
Round O, SC
- Average pressure in September: 30"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.97"Hg).
Average wind speed in September
Round O, SC
- Average wind speed in September: 5.3mph
The windiest month (with the highest average wind speed) is April (6.7mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).
Average humidity in September
Round O, SC
- Average humidity in September: 76%
The months with the highest relative humidity are August and December (77%).
The months with the lowest relative humidity are January, March and November (72%).
Average rainfall in September
Round O, SC
- Average rainfall in September: 1.89"
The wettest month (with the highest rainfall) is August (3.15").
The driest month (with the least rainfall) is November (0.75").
Average rainfall days in September
Round O, SC
- Average rainfall days in September: 14.2 days
The month with the highest number of rainy days is July (21.1 days).
The month with the least rainy days is November (6.2 days).
Average snowfall in September
Round O, SC
- Average snowfall in September: 0"
The months with the highest snowfall are January and February (0.12").
The months with the least snowfall are March, April, May, June, July, August, September, October, November and December (0").
Average snowfall days in September
Round O, SC
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (0.4 days).
The months with the least snowfall days are April, May, June, July, August, September, October and November (0 days).
Average daylight in September /
Average sunshine in September
Round O, SC
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 18min).
The month with the shortest days is December (Average daylight: 10h and 0min).
- Average sunshine in September: 8h and 4min
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 30min).
Average sunshine days in September
Round O, SC
- Average sunshine days in September: 13.5 days
The month with the most sunshine days is November (21.1 days).
The month with the least sunshine days is July (6.9 days).
Average UV index in September
Round O, SC
- Average UV index in September: 6
The months with the highest UV index are June, July and August (UV index 7).
The months with the lowest UV index are January and December (UV index 3).
Average cloud cover in September
Round O, SC
- Average cloud cover in September: 31
The month with the most cloud cover is December (Cloud cover 42).
The months with the least cloud cover are July and October (Cloud cover 29).
Average visibility in September
Round O, SC
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is May (5mi).
Round O, South Carolina, USA
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