September weather forecastMarion, SD
September
Weather in September
The first month of the autumn, September, is still a warm month in Marion, South Dakota, with an average temperature varying between 54°F (12.2°C) and 74.7°F (23.7°C).Temperature
The shift from August to September includes a minor decrease in the average high-temperature, lightly dropping from a warm 81.7°F (27.6°C) to a still moderately hot 74.7°F (23.7°C). An average low-temperature of 54°F (12.2°C) is observed during September nights.Humidity
In Marion, the average relative humidity in September is 70%.Rainfall
In Marion, during September, the rain falls for 10.5 days and regularly aggregates up to 1.61" (41mm) of precipitation. Throughout the year, in Marion, there are 111.7 rainfall days, and 17.76" (451mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall.Daylight
The average length of the day in September is 12h and 29min.On the first day of the month, sunrise is at 6:53 am and sunset at 8:03 pm. On the last day of September, sunrise is at 7:26 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 reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV rays for ordinary individuals.Note: The maximum daily UV index of 4 during September translates into the following directions:
Prioritize safety - Suggestions to prevent sun damage are offered. The intensity of the Sun's UV radiation during midday suggests reducing time spent outdoors. Enhance your sun protection with tightly woven, yet airy clothing.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Marion, SD
- Average high temperature in September: 74.7°F
The warmest month (with the highest average high temperature) is July (83.3°F).
The month with the lowest average high temperature is January (24.3°F).
- Average low temperature in September: 54°F
The month with the highest average low temperature is July (63.7°F).
The coldest month (with the lowest average low temperature) is January (10.8°F).
Average pressure in September
Marion, SD
- Average pressure in September: 29.98"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.85"Hg).
Average wind speed in September
Marion, SD
- Average wind speed in September: 9.3mph
The windiest month (with the highest average wind speed) is April (11.2mph).
The calmest month (with the lowest average wind speed) is July (7.9mph).
Average humidity in September
Marion, SD
- Average humidity in September: 70%
The month with the highest relative humidity is January (87%).
The month with the lowest relative humidity is October (66%).
Average rainfall in September
Marion, SD
- Average rainfall in September: 1.61"
The wettest month (with the highest rainfall) is June (2.91").
The driest months (with the least rainfall) are January, February and November (0.47").
Average rainfall days in September
Marion, SD
- Average rainfall days in September: 10.5 days
The months with the highest number of rainy days are May and June (16 days).
The month with the least rainy days is February (2.5 days).
Average snowfall in September
Marion, SD
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.64").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Marion, SD
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (9.5 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Marion, SD
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 24min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- 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: 4h and 12min).
Average sunshine days in September
Marion, SD
- Average sunshine days in September: 17.5 days
The month with the most sunshine days is November (22.5 days).
The month with the least sunshine days is June (11.5 days).
Average UV index in September
Marion, SD
- Average UV index in September: 4
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is November (UV index 1).
Average cloud cover in September
Marion, SD
- Average cloud cover in September: 28
The month with the most cloud cover is January (Cloud cover 54).
The month with the least cloud cover is July (Cloud cover 25).
Average visibility in September
Marion, SD
- 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).
