Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
Mattoon's progression into September involves a gentle drop in the average high-temperature, from a warm 77.7°F (25.4°C) in August to a pleasant 70°F (21.1°C). Throughout September, an average low-temperature of 50.7°F (10.4°C) is experienced.Humidity
In Mattoon, the average relative humidity in September is 79%.Rainfall
In Mattoon, in September, during 11.7 rainfall days, 1.61" (41mm) of precipitation is typically accumulated. Throughout the year, there are 126.9 rainfall days, and 23.03" (585mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall in Mattoon.Daylight
The average length of the day in September in Mattoon is 12h and 31min.On the first day of September, sunrise is at 6:19 am and sunset at 7:32 pm. On the last day of the month, sunrise is at 6:53 am and sunset at 6:37 pm CDT.
Sunshine
The average sunshine in September is 8.4h.UV index
The average daily maximum UV index in September is 3. A UV Index value of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV radiation for the average person.Note: The maximum daily UV index of 3 during September translates into the following directions:
Ensure safety - Sun damage prevention is strongly urged. Solar radiation is at its peak intensity during midday, so it's advisable to stay indoors or in the shade. Wearing sunglasses with both UVA and UVB protection effectively reduces sun-induced eye damage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature in Mattoon?
What is the average humidity in September in Mattoon?
How much does it rain in Mattoon in September?
When it does not snow in Mattoon?
Does it snow in Mattoon in September?
What is the average length of the day in September in Mattoon?
What time are sunrise and sunset in September in Mattoon?
How many hours of sunshine does Mattoon have in September?
How high is the UV index in September in Mattoon?
Average temperature in September
Mattoon, WI
- Average high temperature in September: 70°F
The warmest month (with the highest average high temperature) is July (79.3°F).
The month with the lowest average high temperature is January (22.3°F).
- Average low temperature in September: 50.7°F
The month with the highest average low temperature is July (59°F).
The coldest month (with the lowest average low temperature) is January (11.5°F).
Average pressure in September
Mattoon, WI
- Average pressure in September: 30.02"Hg
The months with the highest atmospheric pressure are February and March (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Mattoon, WI
- Average wind speed in September: 7.3mph
The windiest month (with the highest average wind speed) is April (9.1mph).
The calmest month (with the lowest average wind speed) is August (6.7mph).
Average humidity in September
Mattoon, WI
- Average humidity in September: 79%
The months with the highest relative humidity are January and February (88%).
The months with the lowest relative humidity are April and May (75%).
Average rainfall in September
Mattoon, WI
- Average rainfall in September: 1.61"
The wettest month (with the highest rainfall) is May (3.19").
The driest months (with the least rainfall) are January and February (1.02").
Average rainfall days in September
Mattoon, WI
- Average rainfall days in September: 11.7 days
The month with the highest number of rainy days is May (15.1 days).
The months with the least rainy days are January and February (4.3 days).
Average snowfall in September
Mattoon, WI
- Average snowfall in September: 0"
The month with the highest snowfall is January (5.28").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Mattoon, WI
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (15.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Mattoon, WI
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 36min).
The month with the shortest days is December (Average daylight: 8h and 48min).
- Average sunshine in September: 8h and 2min
The month with the most sunshine is July (Average sunshine: 10h and 6min).
The month with the least sunshine is February (Average sunshine: 3h and 30min).
Average sunshine days in September
Mattoon, WI
- Average sunshine days in September: 16 days
The month with the most sunshine days is November (16.6 days).
The month with the least sunshine days is April (12.7 days).
Average UV index in September
Mattoon, WI
- Average UV index in September: 3
The months with the highest UV index are June, July and August (UV index 5).
The months with the lowest UV index are January, November and December (UV index 1).
Average cloud cover in September
Mattoon, WI
- Average cloud cover in September: 37
The months with the most cloud cover are January and February (Cloud cover 63).
The month with the least cloud cover is July (Cloud cover 33).
Average visibility in September
Mattoon, WI
- Average visibility in September: 5mi
The months with the highest visibility are March, April, May, June, July, October, November and December (6mi).
The months with the lowest visibility are January, February, August and September (5mi).
Mattoon, Wisconsin, USA
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