September weather forecastHenderson, KY
September
Weather in September
September marks a gradual transition from summer to fall with average temperatures dropping from 79.7°F (26.5°C) to 61°F (16.1°C), and decreased daylight hours. This period brings vibrancy, with the onset of fall foliage while still providing pleasurable weather conditions for outdoor activities. Rainfall reduces to its lowest point for the year, leading to several long, dry and sunny days. The breeze starts to pick up by late September, bringing in the cool of the fall. Though sunshine hours start to taper off, the UV index remains relatively elevated.Temperature
The advent of September brings an average high-temperature of a still moderately hot 79.7°F (26.5°C), almost identical to the preceding month. Throughout the September nights, Henderson encounters a low-temperature of 61°F (16.1°C).Humidity
In September, the average relative humidity is 73%.Rainfall
The month with the least rainfall is September, when the rain falls for 9.9 days and typically collects 0.67" (17mm) of precipitation.Snowfall
April through October are months without snowfall.Daylight
In September, the average length of the day is 12h and 25min.On the first day of the month, sunrise is at 6:21 am and sunset at 7:19 pm. On the last day of September, sunrise is at 6:45 am and sunset at 6:34 pm CDT.
Sunshine
In Henderson, the average sunshine in September is 9.1h.UV index
In September, the average daily maximum UV index is 5. A UV Index estimate of 3 to 5 represents a medium health hazard from unsafe exposure to UV radiation for average individuals.Note: The daily high UV index of 5 in September translates into this advice:
Exercise prevention - Protecting skin and eyes from harm is required. The Sun's radiation is especially intense around midday; try to stay in shade during this period. Sun-related eye harm can be minimized with proper sunglasses offering UVA and UVB coverage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Henderson, KY
- Average high temperature in September: 79.7°F
The warmest month (with the highest average high temperature) is July (85.5°F).
The month with the lowest average high temperature is January (39.4°F).
- Average low temperature in September: 61°F
The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (26.8°F).
Average pressure in September
Henderson, KY
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).
Average wind speed in September
Henderson, KY
- Average wind speed in September: 6.6mph
The windiest month (with the highest average wind speed) is February (10.1mph).
The calmest months (with the lowest average wind speed) are July and August (5.8mph).
Average humidity in September
Henderson, KY
- Average humidity in September: 73%
The month with the highest relative humidity is May (80%).
The month with the lowest relative humidity is October (70%).
Average rainfall in September
Henderson, KY
- Average rainfall in September: 0.67"
The wettest month (with the highest rainfall) is April (1.65").
The driest month (with the least rainfall) is September (0.67").
Average rainfall days in September
Henderson, KY
- Average rainfall days in September: 9.9 days
The months with the highest number of rainy days are May and July (14.4 days).
The month with the least rainy days is November (7.8 days).
Average snowfall in September
Henderson, KY
- Average snowfall in September: 0"
The month with the highest snowfall is January (0.63").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Henderson, KY
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (5 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Henderson, 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: 9h and 6min
The months with the most sunshine are June, July and August (Average sunshine: 10h and 36min).
The month with the least sunshine is January (Average sunshine: 4h and 30min).
Average sunshine days in September
Henderson, KY
- Average sunshine days in September: 17.5 days
The month with the most sunshine days is October (21.3 days).
The month with the least sunshine days is July (13.1 days).
Average UV index in September
Henderson, KY
- 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, February and December (UV index 2).
Average cloud cover in September
Henderson, KY
- Average cloud cover in September: 28
The month with the most cloud cover is January (Cloud cover 52).
The month with the least cloud cover is June (Cloud cover 27).
Average visibility in September
Henderson, KY
- 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).
