September weather forecastSergeant Bluff, IA
September
Weather in September
September, the first month of the autumn in Sergeant Bluff, is also a moderately hot month, with an average temperature varying between 55.4°F (13°C) and 75.6°F (24.2°C).Temperature
The start of September signals a gentle decrease in the average high-temperature, transitioning from a warm 81.9°F (27.7°C) in August to a still moderately hot 75.6°F (24.2°C). September nights are marked by an average temperature drop to a refreshing 55.4°F (13°C).Humidity
The average relative humidity in September is 71%.Rainfall
In Sergeant Bluff, in September, it is raining for 9.7 days, with typically 1.26" (32mm) of accumulated precipitation. Throughout the year, in Sergeant Bluff, there are 102.3 rainfall days, and 12.91" (328mm) of precipitation is accumulated.Snowfall
May through September are months without snowfall.Daylight
In Sergeant Bluff, the average length of the day in September is 12h and 28min.On the first day of September, sunrise is at 6:51 am and sunset at 7:58 pm. On the last day of the month, sunrise is at 7:22 am and sunset at 7:08 pm CDT.
Sunshine
In September, the average sunshine in Sergeant Bluff is 8.9h.UV index
The average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a moderate health risk from exposure to the Sun's UV radiation for the average person.Note: The daily high UV index of 4 during September translates into the following recommendations:
Make use of precautions - Suggestions to resist sunburn are communicated. To protect against the Sun's most potent rays, avoid direct exposure around midday. For minimizing sun-related eye damage, always choose sunglasses with UVA and UVB coverage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Sergeant Bluff, IA
- Average high temperature in September: 75.6°F
The warmest month (with the highest average high temperature) is July (83.8°F).
The month with the lowest average high temperature is January (27°F).
- Average low temperature in September: 55.4°F
The month with the highest average low temperature is July (64.9°F).
The coldest month (with the lowest average low temperature) is January (13.5°F).
Average pressure in September
Sergeant Bluff, IA
- Average pressure in September: 29.99"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.86"Hg).
Average wind speed in September
Sergeant Bluff, IA
- Average wind speed in September: 8.9mph
The windiest month (with the highest average wind speed) is April (11mph).
The calmest month (with the lowest average wind speed) is July (7.5mph).
Average humidity in September
Sergeant Bluff, IA
- Average humidity in September: 71%
The month with the highest relative humidity is January (83%).
The month with the lowest relative humidity is October (65%).
Average rainfall in September
Sergeant Bluff, IA
- Average rainfall in September: 1.26"
The wettest month (with the highest rainfall) is June (1.85").
The driest months (with the least rainfall) are January and February (0.39").
Average rainfall days in September
Sergeant Bluff, IA
- Average rainfall days in September: 9.7 days
The month with the highest number of rainy days is June (14.6 days).
The month with the least rainy days is January (2.6 days).
Average snowfall in September
Sergeant Bluff, IA
- Average snowfall in September: 0"
The month with the highest snowfall is January (1.77").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Sergeant Bluff, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (8.2 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Sergeant Bluff, IA
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in September: 8h and 54min
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 30min).
Average sunshine days in September
Sergeant Bluff, IA
- Average sunshine days in September: 17.5 days
The month with the most sunshine days is January (22.6 days).
The month with the least sunshine days is June (13.1 days).
Average UV index in September
Sergeant Bluff, IA
- 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 January (UV index 1).
Average cloud cover in September
Sergeant Bluff, IA
- Average cloud cover in September: 29
The month with the most cloud cover is January (Cloud cover 51).
The month with the least cloud cover is July (Cloud cover 25).
Average visibility in September
Sergeant Bluff, 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).





