September weather forecastIrma, WI
September
Weather in September
The first month of the autumn, September, is still a refreshing month in Irma, Wisconsin, with temperature in the range of an average high of 67.1°F (19.5°C) and an average low of 48.6°F (9.2°C).Temperature
September's onset corresponds with a subtle shift in the average high-temperature, slightly moving from a warm 75.7°F (24.3°C) in August to an enjoyable 67.1°F (19.5°C). The average temperature during September nights is registered at a chilly 48.6°F (9.2°C).Humidity
The average relative humidity in September is 80%.Rainfall
In Irma, in September, during 12.7 rainfall days, 1.57" (40mm) of precipitation is typically accumulated. Throughout the year, there are 132.2 rainfall days, and 23.15" (588mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall in Irma.Daylight
In Irma, the average length of the day in September is 12h and 31min.On the first day of the month, sunrise is at 6:21 am and sunset at 7:35 pm. On the last day of September, sunrise is at 6:56 am and sunset at 6:40 pm CDT.
Sunshine
The average sunshine in September is 7.7h.UV index
In September, the average daily maximum UV index in Irma is 3. A UV Index estimate of 3 to 5 represents a moderate health risk from exposure to the Sun's UV radiation for the ordinary person.Note: In September, an average UV index of 3 transforms into the following instructions:
Ensure safety - Recommendations to avert sunburn are presented. It's crucial to reduce time in the direct Sun around mid-day due to the intense solar radiation. 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
Irma, WI
- Average high temperature in September: 67.1°F
The warmest month (with the highest average high temperature) is July (78.1°F).
The month with the lowest average high temperature is January (18.9°F).
- Average low temperature in September: 48.6°F
The month with the highest average low temperature is July (57°F).
The coldest month (with the lowest average low temperature) is January (7.3°F).
Average pressure in September
Irma, WI
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is February (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Irma, WI
- Average wind speed in September: 7.4mph
The windiest month (with the highest average wind speed) is April (8.6mph).
The calmest month (with the lowest average wind speed) is August (6.7mph).
Average humidity in September
Irma, WI
- Average humidity in September: 80%
The month with the highest relative humidity is February (92%).
The month with the lowest relative humidity is May (73%).
Average rainfall in September
Irma, WI
- Average rainfall in September: 1.57"
The wettest month (with the highest rainfall) is June (2.95").
The driest month (with the least rainfall) is January (1.1").
Average rainfall days in September
Irma, WI
- Average rainfall days in September: 12.7 days
The month with the highest number of rainy days is June (16.7 days).
The month with the least rainy days is February (2.8 days).
Average snowfall in September
Irma, WI
- Average snowfall in September: 0"
The month with the highest snowfall is February (8.35").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Irma, WI
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (22.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Irma, WI
- Average daylight in September: 12h and 30min
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: 7h and 42min
The month with the most sunshine is July (Average sunshine: 9h and 36min).
The month with the least sunshine is January (Average sunshine: 2h and 18min).
Average sunshine days in September
Irma, WI
- Average sunshine days in September: 14.5 days
The month with the most sunshine days is September (14.5 days).
The month with the least sunshine days is February (8 days).
Average UV index in September
Irma, 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, February, March, November and December (UV index 1).
Average cloud cover in September
Irma, WI
- Average cloud cover in September: 45
The months with the most cloud cover are January and February (Cloud cover 79).
The month with the least cloud cover is July (Cloud cover 40).
Average visibility in September
Irma, WI
- Average visibility in September: 5mi
The months with the highest visibility are May and October (6mi).
The months with the lowest visibility are January and February (4mi).





