September weather forecastHenry, SD
September
Weather in September
September, the first month of the autumn in Henry, is also an agreeable month, with an average temperature varying between 71.6°F (22°C) and 51.3°F (10.7°C).Temperature
September's arrival comes with a mild decrease in the average high-temperature, moving subtly from a warm 80.1°F (26.7°C) in August to a pleasant 71.6°F (22°C). Henry in September anticipates an average nighttime temperature of 51.3°F (10.7°C).Humidity
September and October, with an average relative humidity of 68%, are the least humid months in Henry.Rainfall
In September, the rain falls for 10.4 days. Throughout September, 1.57" (40mm) of precipitation is accumulated. Throughout the year, in Henry, there are 112.3 rainfall days, and 18.78" (477mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall.Daylight
The average length of the day in September is 12h and 31min.On the first day of September in Henry, sunrise is at 6:53 am and sunset at 8:06 pm. On the last day of the month, sunrise is at 7:27 am and sunset at 7:11 pm CDT.
Sunshine
The average sunshine in September is 8.8h.UV index
In September, the average daily maximum UV index is 4. A UV Index of 3 to 5 symbolizes a moderate health risk from unsafe exposure to UV radiation for the ordinary person.Note: The maximum UV index, 4 during September, leads to the following recommendations:
Exercise prudence. Persons with fair skin could be burned in under 30 minutes. Around midday, solar radiation is most harmful; hence, exposure should be limited. 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. Take heed! Reflection from the snow can almost amplify the Sun's UV radiation by double.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Henry, SD
- Average high temperature in September: 71.6°F
The warmest month (with the highest average high temperature) is July (80.8°F).
The month with the lowest average high temperature is January (19.4°F).
- Average low temperature in September: 51.3°F
The month with the highest average low temperature is July (60.8°F).
The coldest month (with the lowest average low temperature) is January (5.5°F).
Average pressure in September
Henry, SD
- Average pressure in September: 29.97"Hg
The months with the highest atmospheric pressure are January and February (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.85"Hg).
Average wind speed in September
Henry, SD
- Average wind speed in September: 10mph
The windiest month (with the highest average wind speed) is April (11.6mph).
The calmest month (with the lowest average wind speed) is July (8.5mph).
Average humidity in September
Henry, SD
- Average humidity in September: 68%
The month with the highest relative humidity is January (90%).
The months with the lowest relative humidity are September and October (68%).
Average rainfall in September
Henry, SD
- Average rainfall in September: 1.57"
The wettest month (with the highest rainfall) is June (3.19").
The driest months (with the least rainfall) are January and February (0.59").
Average rainfall days in September
Henry, SD
- Average rainfall days in September: 10.4 days
The month with the highest number of rainy days is June (17.2 days).
The month with the least rainy days is February (2.7 days).
Average snowfall in September
Henry, SD
- Average snowfall in September: 0"
The months with the highest snowfall are January and December (3.74").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Henry, SD
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is January (14.4 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Henry, SD
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 30min).
The month with the shortest days is December (Average daylight: 8h and 54min).
- Average sunshine in September: 8h and 48min
The month with the most sunshine is July (Average sunshine: 10h and 42min).
The month with the least sunshine is January (Average sunshine: 3h and 36min).
Average sunshine days in September
Henry, SD
- Average sunshine days in September: 18.2 days
The month with the most sunshine days is October (19.1 days).
The month with the least sunshine days is June (10.3 days).
Average UV index in September
Henry, SD
- Average UV index in September: 4
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Henry, SD
- Average cloud cover in September: 30
The month with the most cloud cover is January (Cloud cover 63).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in September
Henry, SD
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).





