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
September's arrival coincides with a soft drop in the average high-temperature, subtly decreasing from August's warm 77°F (25°C) to a pleasant 69.6°F (20.9°C). Nighttime temperature lowers to an average of 52.7°F (11.5°C) in September.Humidity
The average relative humidity in September is 80%.Rainfall
In Brillion, during September, the rain falls for 12.5 days and regularly aggregates up to 1.34" (34mm) of precipitation. Throughout the year, there are 125 rainfall days, and 18.07" (459mm) of precipitation is accumulated.Snowfall
In Brillion, Wisconsin, snow does not fall in June through September.Daylight
In Brillion, the average length of the day in September is 12h and 30min.On the first day of September, sunrise is at 6:16 am and sunset at 7:27 pm. On the last day of the month, sunrise is at 6:49 am and sunset at 6:34 pm CDT.
Sunshine
In September, the average sunshine is 8.5h.UV index
In September, the average daily maximum UV index is 3. A UV Index reading of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV rays for average individuals.Note: In September, the maximum UV index of 3 suggests this advice:
Undertake protective steps - Recommendations to avoid sunburn are issued. Avoiding direct sunlight during midday hours helps reduce the risk from intense UV radiation. Stay sun-safe with clothing that is both closely woven and worn loosely.
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Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in September?
What is the average humidity in September?
How much does it rain in September?
When it does not snow?
Does it snow in September?
What is the average length of the day in September?
When are sunrise and sunset in September?
How long on average sun shines in September?
How high is the UV index in September?
Average temperature in September
Brillion, WI
- Average high temperature in September: 69.6°F
The warmest month (with the highest average high temperature) is July (78.3°F).
The month with the lowest average high temperature is January (23.2°F).
- Average low temperature in September: 52.7°F
The month with the highest average low temperature is July (61°F).
The coldest month (with the lowest average low temperature) is January (12°F).
Average pressure in September
Brillion, 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
Brillion, WI
- Average wind speed in September: 8mph
The windiest months (with the highest average wind speed) are January and February (10.3mph).
The calmest months (with the lowest average wind speed) are July and August (7.1mph).
Average humidity in September
Brillion, WI
- Average humidity in September: 80%
The months with the highest relative humidity are January and February (88%).
The month with the lowest relative humidity is April (76%).
Average rainfall in September
Brillion, WI
- Average rainfall in September: 1.34"
The wettest month (with the highest rainfall) is May (2.48").
The driest month (with the least rainfall) is February (0.79").
Average rainfall days in September
Brillion, WI
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is July (14.9 days).
The month with the least rainy days is January (3.8 days).
Average snowfall in September
Brillion, WI
- Average snowfall in September: 0"
The month with the highest snowfall is January (3.35").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Brillion, WI
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (13.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Brillion, WI
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 30min).
The month with the shortest days is December (Average daylight: 8h and 54min).
- Average sunshine in September: 8h and 3min
The month with the most sunshine is July (Average sunshine: 10h and 18min).
The month with the least sunshine is February (Average sunshine: 3h and 24min).
Average sunshine days in September
Brillion, WI
- Average sunshine days in September: 15.7 days
The month with the most sunshine days is November (17.2 days).
The month with the least sunshine days is July (12.6 days).
Average UV index in September
Brillion, 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
Brillion, WI
- Average cloud cover in September: 34
The month with the most cloud cover is January (Cloud cover 64).
The month with the least cloud cover is July (Cloud cover 31).
Average visibility in September
Brillion, WI
- Average visibility in September: 6mi
The months with the highest visibility are March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January and February (5mi).
Brillion, Wisconsin, USA
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