September weather forecastHepburn, IA
September
Weather in September
The first month of the autumn, September, is still a warm month in Hepburn, Iowa, with temperature in the range of an average high of 76.6°F (24.8°C) and an average low of 57°F (13.9°C).Temperature
The transition to September results in a modest reduction in average high-temperature, moving from 82.2°F (27.9°C) in August to a still warm 76.6°F (24.8°C). An average low-temperature of 57°F (13.9°C) is recorded in the month of September.Humidity
The average relative humidity in September is 75%.Rainfall
In Hepburn, during September, the rain falls for 10.1 days and regularly aggregates up to 1.34" (34mm) of precipitation. Throughout the year, there are 114.9 rainfall days, and 18.39" (467mm) of precipitation is accumulated.Snowfall
May through September are months without snowfall.Daylight
The average length of the day in September is 12h and 27min.On the first day of September, sunrise is at 6:47 am and sunset at 7:51 pm. On the last day of the month, sunrise is at 7:16 am and sunset at 7:03 pm CDT.
Sunshine
In Hepburn, the average sunshine in September is 9.3h.UV index
In September, the average daily maximum UV index is 5. A UV Index value of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for average individuals.Note: The daily high UV index of 5 in September translates into this advice:
Take necessary precautions - Defending against sun damage is advocated. UV radiation is strongest from the Sun during midday; protect yourself by staying in shaded areas. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Hepburn, IA
- Average high temperature in September: 76.6°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 (31.1°F).
- Average low temperature in September: 57°F
The month with the highest average low temperature is July (66.6°F).
The coldest month (with the lowest average low temperature) is January (17.2°F).
Average pressure in September
Hepburn, IA
- Average pressure in September: 30"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.87"Hg).
Average wind speed in September
Hepburn, IA
- Average wind speed in September: 8mph
The windiest month (with the highest average wind speed) is March (10.3mph).
The calmest month (with the lowest average wind speed) is July (6.7mph).
Average humidity in September
Hepburn, IA
- Average humidity in September: 75%
The month with the highest relative humidity is January (80%).
The month with the lowest relative humidity is October (69%).
Average rainfall in September
Hepburn, IA
- Average rainfall in September: 1.34"
The wettest month (with the highest rainfall) is June (3.39").
The driest month (with the least rainfall) is February (0.43").
Average rainfall days in September
Hepburn, IA
- Average rainfall days in September: 10.1 days
The month with the highest number of rainy days is May (16.7 days).
The month with the least rainy days is February (3.4 days).
Average snowfall in September
Hepburn, IA
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.17").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Hepburn, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (7.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Hepburn, 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 18min).
- 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 36min).
Average sunshine days in September
Hepburn, IA
- 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 (12.3 days).
Average UV index in September
Hepburn, IA
- Average UV index in September: 5
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
Hepburn, IA
- Average cloud cover in September: 28
The month with the most cloud cover is January (Cloud cover 49).
The month with the least cloud cover is July (Cloud cover 27).
Average visibility in September
Hepburn, 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).





