September weather forecastSouth Williamson, KY
September
Weather in September
The first month of the autumn, September, is still a warm month in South Williamson, Kentucky, with an average temperature ranging between max 78.6°F (25.9°C) and min 56.8°F (13.8°C).Temperature
As South Williamson enters September, the average high-temperature subtly lowers from the a warm 84.4°F (29.1°C) of August to a still moderately hot 78.6°F (25.9°C). South Williamson documents a substantial shift from daytime warmth, recording an average nighttime temperature of 56.8°F (13.8°C) in September.Humidity
In September, the average relative humidity is 76%.Rainfall
September is the month with the least rainfall. Rain falls for 12.5 days and accumulates 1.46" (37mm) of precipitation.Snowfall
In South Williamson, snow does not fall in June through September.Daylight
In South Williamson, the average length of the day in September is 12h and 25min.On the first day of the month, sunrise is at 6:59 am and sunset at 7:57 pm. On the last day of September, in South Williamson, sunrise is at 7:24 am and sunset at 7:13 pm EDT.
Sunshine
In September, the average sunshine is 8.3h.UV index
The average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV rays for the ordinary person.Note: In September, an average UV index of 4 transforms into the following instructions:
Undertake precautions - Guarding against sun damage is counselled. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
South Williamson, KY
- Average high temperature in September: 78.6°F
The warmest month (with the highest average high temperature) is July (86°F).
The month with the lowest average high temperature is January (40.1°F).
- Average low temperature in September: 56.8°F
The month with the highest average low temperature is July (63.1°F).
The coldest month (with the lowest average low temperature) is January (26.8°F).
Average pressure in September
South Williamson, KY
- Average pressure in September: 30.06"Hg
The month with the highest atmospheric pressure is November (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.98"Hg).
Average wind speed in September
South Williamson, KY
- Average wind speed in September: 4.2mph
The windiest month (with the highest average wind speed) is April (6.4mph).
The calmest month (with the lowest average wind speed) is August (3.9mph).
Average humidity in September
South Williamson, KY
- Average humidity in September: 76%
The month with the highest relative humidity is February (81%).
The months with the lowest relative humidity are July, August and November (75%).
Average rainfall in September
South Williamson, KY
- Average rainfall in September: 1.46"
The wettest months (with the highest rainfall) are February and May (3.27").
The driest month (with the least rainfall) is September (1.46").
Average rainfall days in September
South Williamson, KY
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is May (18.2 days).
The month with the least rainy days is November (10.1 days).
Average snowfall in September
South Williamson, KY
- Average snowfall in September: 0"
The month with the highest snowfall is February (4.09").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
South Williamson, KY
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (9.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
South Williamson, KY
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in September: 8h and 18min
The month with the most sunshine is August (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days in September
South Williamson, KY
- Average sunshine days in September: 15.5 days
The month with the most sunshine days is October (17.7 days).
The month with the least sunshine days is May (10.5 days).
Average UV index in September
South Williamson, KY
- Average UV index in September: 4
The months with the highest UV index are June and August (UV index 6).
The months with the lowest UV index are January, February and December (UV index 2).
Average cloud cover in September
South Williamson, KY
- Average cloud cover in September: 35
The month with the most cloud cover is January (Cloud cover 59).
The month with the least cloud cover is August (Cloud cover 31).
Average visibility in September
South Williamson, KY
- Average visibility in September: 5mi
The months with the highest visibility are April and November (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October and December (5mi).
