September weather forecastSeymour, IL
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Seymour, Illinois, with an average temperature ranging between min 58.3°F (14.6°C) and max 76.1°F (24.5°C).Temperature
In September, Seymour experiences a barely noticeable shift in meteorological conditions, with average high-temperatures moving from 80.2°F (26.8°C) in August to a still warm 76.1°F (24.5°C). Throughout September, the average low-temperature records at a refreshing 58.3°F (14.6°C).Humidity
In Seymour, the average relative humidity in September is 76%.Rainfall
In Seymour, during September, the rain falls for 12.8 days and regularly aggregates up to 1.77" (45mm) of precipitation. Throughout the year, there are 152.9 rainfall days, and 29.72" (755mm) of precipitation is accumulated.Snowfall
In Seymour, snow does not fall in May through September.Daylight
In September, the average length of the day is 12h and 26min.On the first day of the month, sunrise is at 6:22 am and sunset at 7:24 pm. On the last day of September, sunrise is at 6:49 am and sunset at 6:37 pm CDT.
Sunshine
In September, the average sunshine is 8.9h.UV index
The average daily maximum UV index in September is 5. A UV Index estimate of 3 to 5 represents a medium vulnerability from unsafe exposure to UV radiation for average individuals.Note: In September, a daily UV index of 5 turns into the following recommendations:
Ensure safety - Sun damage prevention is strongly urged. It's recommended to limit sun exposure when its radiation is at its peak during midday. Counter UV radiation's ill effects with clothing designed for sun safety and UV-resistant eyewear.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Seymour, IL
- Average high temperature in September: 76.1°F
The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (31.5°F).
- Average low temperature in September: 58.3°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 (19.9°F).
Average pressure in September
Seymour, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Seymour, IL
- Average wind speed in September: 7.4mph
The windiest month (with the highest average wind speed) is January (10.9mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity in September
Seymour, IL
- Average humidity in September: 76%
The month with the highest relative humidity is July (85%).
The month with the lowest relative humidity is October (70%).
Average rainfall in September
Seymour, IL
- Average rainfall in September: 1.77"
The wettest month (with the highest rainfall) is May (3.9").
The driest month (with the least rainfall) is December (1.65").
Average rainfall days in September
Seymour, IL
- Average rainfall days in September: 12.8 days
The month with the highest number of rainy days is May (18.8 days).
The month with the least rainy days is February (6.3 days).
Average snowfall in September
Seymour, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (4.25").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Seymour, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (11.4 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
Seymour, IL
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in September: 8h and 54min
The month with the most sunshine is June (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days in September
Seymour, IL
- Average sunshine days in September: 15.3 days
The month with the most sunshine days is November (18 days).
The month with the least sunshine days is June (10.2 days).
Average UV index in September
Seymour, IL
- 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
Seymour, IL
- Average cloud cover in September: 31
The month with the most cloud cover is January (Cloud cover 57).
The months with the least cloud cover are August and September (Cloud cover 31).
Average visibility in September
Seymour, IL
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).





