September weather forecastSeneca, SC
September
Weather in September
The first month of the autumn, September, is still a warm month in Seneca, South Carolina, with an average temperature fluctuating between 82.8°F (28.2°C) and 62.1°F (16.7°C).Temperature
September brings a marginal elevation to a warm 82.8°F (28.2°C) from August's 88°F (31.1°C) in Seneca's average high-temperatures. Seneca's nights in September experience an average temperature drop to a comfortable 62.1°F (16.7°C).Heat index
For September, the heat index is computed to be a hot 87.8°F (31°C). A sense of exhaustion might occur with extended exposure and activity, potentially causing heat cramps.Heat index data is primarily for areas with shade and subjected to light winds. The heat index values could be amplified by up to 15 Fahrenheit (8 Celsius) degrees in direct sunlight.
Note: The heat index, also known as 'real feel' or 'felt air temperature', is a value derived by merging air temperature with the humidity to convey how the climate feels. The influence of weather is personal, with varied individuals experiencing it differently due to differences in body mass, stature, and physical exertion levels. Recognize that direct exposure to the sun can escalate the heat effect, potentially adding 15 Fahrenheit (8 Celsius) degrees to the heat index. Heat index values are extremely significant for babies and toddlers. Young individuals are generally in more danger than adults due to their lower capacity to sweat. Moreover, their large skin surface in relation to their small bodies and the increased heat generation from their activities makes them more vulnerable.
Humidity
In September, the average relative humidity is 72%.Rainfall
The month with the least rainfall is September, when the rain falls for 12.5 days and typically collects 1.73" (44mm) of precipitation.Snowfall
In Seneca, snow does not fall in April through October.Daylight
In September, the average length of the day is 12h and 23min.On the first day of September, sunrise is at 7:05 am and sunset at 7:57 pm. On the last day of the month, sunrise is at 7:26 am and sunset at 7:16 pm EDT.
Sunshine
The average sunshine in September is 8.7h.UV index
In Seneca, the average daily maximum UV index in September is 5. A UV Index of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV radiation for the ordinary person.Note: The maximum daily UV index of 5 in September interprets into the following recommendations:
Take precautions - Protection against sun damage is advised. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Seneca, SC
- Average high temperature in September: 82.8°F
The warmest month (with the highest average high temperature) is July (89.6°F).
The month with the lowest average high temperature is January (49.6°F).
- Average low temperature in September: 62.1°F
The month with the highest average low temperature is July (68°F).
The coldest month (with the lowest average low temperature) is January (33.4°F).
Average pressure in September
Seneca, SC
- Average pressure in September: 30.03"Hg
The months with the highest atmospheric pressure are January and November (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.99"Hg).
Average wind speed in September
Seneca, SC
- Average wind speed in September: 4.6mph
The windiest month (with the highest average wind speed) is February (6.3mph).
The calmest month (with the lowest average wind speed) is August (4.1mph).
Average humidity in September
Seneca, SC
- Average humidity in September: 72%
The month with the highest relative humidity is December (77%).
The month with the lowest relative humidity is July (70%).
Average rainfall in September
Seneca, SC
- Average rainfall in September: 1.73"
The wettest month (with the highest rainfall) is December (4.21").
The driest month (with the least rainfall) is September (1.73").
Average rainfall days in September
Seneca, SC
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is July (17.8 days).
The month with the least rainy days is October (9.5 days).
Average snowfall in September
Seneca, SC
- Average snowfall in September: 0"
The month with the highest snowfall is December (2.05").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Seneca, SC
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (1.4 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
Seneca, SC
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 9h and 54min).
- Average sunshine in September: 8h and 42min
The month with the most sunshine is July (Average sunshine: 11h and 6min).
The month with the least sunshine is December (Average sunshine: 5h and 24min).
Average sunshine days in September
Seneca, SC
- Average sunshine days in September: 15.3 days
The month with the most sunshine days is October (20.5 days).
The month with the least sunshine days is July (10.5 days).
Average UV index in September
Seneca, 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
Seneca, SC
- Average cloud cover in September: 30
The months with the most cloud cover are February and December (Cloud cover 41).
The months with the least cloud cover are June and July (Cloud cover 27).
Average visibility in September
Seneca, 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).





