September weather forecastSwansea, SC
September
Weather in September
September, the first month of the autumn in Swansea, is still a warm month, with temperature in the range of an average high of 84.2°F (29°C) and an average low of 67.1°F (19.5°C).Temperature
Swansea marks the onset of September with an average high-temperature of a moderately hot 84.2°F (29°C), subtly divergent from August's 89.2°F (31.8°C). The low-temperature averages to an enjoyable 67.1°F (19.5°C) during the nights of September.Heat index
During September, the heat index is estimated at a tropical 91.4°F (33°C). Exercise special caution, heat exhaustion and heat cramps are probable. Prolonged activity may induce heatstroke.In terms of the heat index, values are set with light wind and shade conditions in mind. Heat index values can rise by 15 Fahrenheit (8 Celsius) degrees when in direct sunlight.
Note: The heat index, also known as 'apparent temperature' or 'feels like', is an indicator that blends the effects of temperature and humidity to depict perceived warmth. The effect is experienced differently by individuals, hinging on unique characteristics such as body mass, stature, and level of activity. In direct sunlight, the heat's impact can be heightened, potentially leading to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold particular significance for children. Children typically face more danger than adults as their sweat production is usually lower. Additionally, the bigger skin surface compared to their small size and the increased heat due to their activeness exacerbate the risk.
Humidity
The average relative humidity in September is 74%.Rainfall
The months with the least rainfall are September and November Rain falls for 14.3 days and accumulates 2.01" (51mm) of rain.Snowfall
In Swansea, snow does not fall in April through November.Daylight
The average length of the day in September in Swansea, South Carolina, is 12h and 22min.On the first day of the month, sunrise is at 6:58 am and sunset at 7:49 pm. On the last day of September, in Swansea, sunrise is at 7:18 am and sunset at 7:09 pm EDT.
Sunshine
In September, the average sunshine is 8.7h.UV index
The average daily maximum UV index in September is 6. A UV Index estimate of 6 to 7 represents a high health hazard from unprotected exposure to Sun's UV rays for ordinary individuals.Note: In September, a daily maximum UV index of 6 leads to the following instructions:
Take precautions and utilize sun safety practices. Protection against skin and eye damage is required. Avoid direct sunlight between the hours of 10 a.m. and 4 p.m., when UV radiation is at its peak. Keep in mind that shade structures may not provide complete protection. Employ a wide-brim hat for potent defense against up to 50% of UV rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Swansea, SC
- Average high temperature in September: 84.2°F
The warmest month (with the highest average high temperature) is July (91°F).
The month with the lowest average high temperature is January (53.2°F).
- Average low temperature in September: 67.1°F
The month with the highest average low temperature is July (73°F).
The coldest month (with the lowest average low temperature) is January (38.1°F).
Average pressure in September
Swansea, SC
- Average pressure in September: 30.01"Hg
The months with the highest atmospheric pressure are January, November and December (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.97"Hg).
Average wind speed in September
Swansea, SC
- Average wind speed in September: 6.2mph
The windiest months (with the highest average wind speed) are February, March and April (8.5mph).
The calmest month (with the lowest average wind speed) is August (5.6mph).
Average humidity in September
Swansea, SC
- Average humidity in September: 74%
The month with the highest relative humidity is December (75%).
The months with the lowest relative humidity are January and November (70%).
Average rainfall in September
Swansea, SC
- Average rainfall in September: 2.01"
The wettest month (with the highest rainfall) is December (3.86").
The driest months (with the least rainfall) are September and November (2.01").
Average rainfall days in September
Swansea, SC
- Average rainfall days in September: 14.3 days
The month with the highest number of rainy days is July (19.9 days).
The months with the least rainy days are October and November (9 days).
Average snowfall in September
Swansea, SC
- Average snowfall in September: 0"
The months with the highest snowfall are January and February (0.31").
The months with the least snowfall are April, May, June, July, August, September, October and November (0").
Average snowfall days in September
Swansea, SC
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (0.7 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
Swansea, 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: 10h and 0min).
- Average sunshine in September: 8h and 42min
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
Swansea, SC
- Average sunshine days in September: 14 days
The month with the most sunshine days is October (20.5 days).
The month with the least sunshine days is July (8.4 days).
Average UV index in September
Swansea, SC
- Average UV index in September: 6
The months with the highest UV index are June and July (UV index 7).
The months with the lowest UV index are January, February and December (UV index 3).
Average cloud cover in September
Swansea, SC
- Average cloud cover in September: 31
The months with the most cloud cover are February and December (Cloud cover 41).
The months with the least cloud cover are June and October (Cloud cover 28).
Average visibility in September
Swansea, 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).
