September weather forecastIndianola, IA
September
Weather in September
September marks a gentle shift in Indianola, Iowa's climate from sweltering August to a cooler autumn with the average high temperature cooling to 75.7°F (24.3°C). The town starts synchronizing to the rhythm of falling leaves and crisp air. The fledgling phase of fall manifests through subtler mornings and brisk evenings. September witnesses a transition from the lush greenery to a multi-hued foliage vista. As this month culminates, the arrival of a full-fledged fall season becomes imminent.Temperature
September's arrival comes with a mild decrease in the average high-temperature, moving subtly from a moderately hot 81.3°F (27.4°C) in August to a still warm 75.7°F (24.3°C). Indianola reports an average nighttime low-temperature of 55.9°F (13.3°C) in September.Humidity
In Indianola, the average relative humidity in September is 76%.Rainfall
In Indianola, during September, the rain falls for 11.1 days and regularly aggregates up to 1.81" (46mm) of precipitation. Throughout the year, there are 118.9 rainfall days, and 18.62" (473mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall.Daylight
In September, the average length of the day is 12h and 28min.On the first day of September, sunrise is at 6:41 am and sunset at 7:46 pm. On the last day of the month, sunrise is at 7:10 am and sunset at 6:57 pm CDT.
Sunshine
In Indianola, the average sunshine in September is 9.3h.UV index
In Indianola, the average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV radiation for the ordinary person.Note: In September, the UV index of 4 transforms into the following advice:
Take precautions - Protection against sunburn is recommended. Being exposed to the midday Sun can have harmful effects due to strong UV radiation; always take precautions. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Indianola, IA
- Average high temperature in September: 75.7°F
The warmest month (with the highest average high temperature) is July (83.1°F).
The month with the lowest average high temperature is January (28.8°F).
- Average low temperature in September: 55.9°F
The month with the highest average low temperature is July (65.7°F).
The coldest month (with the lowest average low temperature) is January (15.3°F).
Average pressure in September
Indianola, IA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed in September
Indianola, IA
- Average wind speed in September: 8mph
The windiest month (with the highest average wind speed) is January (10.4mph).
The calmest month (with the lowest average wind speed) is August (6.9mph).
Average humidity in September
Indianola, IA
- Average humidity in September: 76%
The months with the highest relative humidity are January and June (82%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Indianola, IA
- Average rainfall in September: 1.81"
The wettest month (with the highest rainfall) is May (3.07").
The driest month (with the least rainfall) is December (0.55").
Average rainfall days in September
Indianola, IA
- Average rainfall days in September: 11.1 days
The months with the highest number of rainy days are May and June (15.9 days).
The month with the least rainy days is January (3.4 days).
Average snowfall in September
Indianola, IA
- Average snowfall in September: 0"
The month with the highest snowfall is February (3.03").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Indianola, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (9.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Indianola, IA
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in September: 9h and 18min
The month with the most sunshine is July (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 18min).
Average sunshine days in September
Indianola, IA
- Average sunshine days in September: 17 days
The month with the most sunshine days is December (21.9 days).
The month with the least sunshine days is June (11 days).
Average UV index in September
Indianola, IA
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in September
Indianola, IA
- Average cloud cover in September: 29
The month with the most cloud cover is January (Cloud cover 53).
The month with the least cloud cover is July (Cloud cover 28).
Average visibility in September
Indianola, IA
- 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).
