September weather forecastUnion Center, SD
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Union Center, South Dakota, with temperature in the range of an average low of 53.4°F (11.9°C) and an average high of 73.8°F (23.2°C).Temperature
The advent of September brings a subtle shift in temperature, with the average high moving from 82.6°F (28.1°C) in August to a still moderately hot 73.8°F (23.2°C). September nights observe an average temperature dip to a fresh 53.4°F (11.9°C).Humidity
August and September, with an average relative humidity of 49%, are the least humid months in Union Center.Rainfall
In Union Center, South Dakota, in September, during 9 rainfall days, 0.83" (21mm) of precipitation is typically accumulated. In Union Center, during the entire year, the rain falls for 126.3 days and collects up to 16.77" (426mm) of precipitation.Snowfall
January through May, September through December are months with snowfall. September is the first month it typically snows. Throughout September, in the average 0.1 snowfall days, it receives 0.04" (1mm) of snow. In Union Center, during the entire year, snow falls for 62.1 days and aggregates up to 36.26" (921mm) of snow.Daylight
In Union Center, the average length of the day in September is 12h and 30min.On the first day of the month, sunrise is at 6:14 am and sunset at 7:26 pm. On the last day of September, sunrise is at 6:48 am and sunset at 6:32 pm MDT.
Sunshine
The average sunshine in September is 10.4h.UV index
In Union Center, the average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a moderate health risk from unsafe exposure to UV radiation for the average person.Note: The UV index of 4 during September leads to these advisories:
Take necessary precautions - Protection from skin and eye injury is mandatory. Direct exposure to the Sun's intense radiation around midday should be avoided for health reasons. Consider a wide-brim hat essential for effective sun defense covering your face, neck, and eyes. Guard yourself! Snow reflection can almost double the UV radiation from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Union Center, SD
- Average high temperature in September: 73.8°F
The warmest month (with the highest average high temperature) is July (84.7°F).
The month with the lowest average high temperature is December (32.2°F).
- Average low temperature in September: 53.4°F
The month with the highest average low temperature is July (62.4°F).
The coldest month (with the lowest average low temperature) is February (18°F).
Average pressure in September
Union Center, SD
- Average pressure in September: 29.93"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.84"Hg).
Average wind speed in September
Union Center, SD
- Average wind speed in September: 9.1mph
The windiest month (with the highest average wind speed) is October (10.4mph).
The calmest months (with the lowest average wind speed) are July and August (8.3mph).
Average humidity in September
Union Center, SD
- Average humidity in September: 49%
The month with the highest relative humidity is January (77%).
The months with the lowest relative humidity are August and September (49%).
Average rainfall in September
Union Center, SD
- Average rainfall in September: 0.83"
The wettest month (with the highest rainfall) is May (2.52").
The driest month (with the least rainfall) is January (0.59").
Average rainfall days in September
Union Center, SD
- Average rainfall days in September: 9 days
The month with the highest number of rainy days is May (17.3 days).
The month with the least rainy days is December (5.8 days).
Average snowfall in September
Union Center, SD
- Average snowfall in September: 0.04"
The month with the highest snowfall is April (8.23").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Union Center, SD
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is February (12.8 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Union Center, 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: 10h and 24min
The month with the most sunshine is August (Average sunshine: 11h and 42min).
The month with the least sunshine is February (Average sunshine: 5h and 54min).
Average sunshine days in September
Union Center, SD
- Average sunshine days in September: 17.7 days
The month with the most sunshine days is November (20 days).
The month with the least sunshine days is May (9.4 days).
Average UV index in September
Union Center, SD
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Union Center, SD
- Average cloud cover in September: 18
The months with the most cloud cover are February and April (Cloud cover 39).
The month with the least cloud cover is August (Cloud cover 16).
Average visibility in September
Union Center, 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).
