September weather forecastMequon, WI
September
Weather in September
September in Mequon, Wisconsin introduces the mellow charm of autumn, bringing a noticeable drop in temperature as the days shorten with highs and lows between 69.8°F (21°C) and 56.5°F (13.6°C). The lazy sunshine drenches the landscape in a golden light, revealing the first signs of fading greens. The pleasant weather draws attention to the state park's allure, filled with migrating birds and colorful foliage. A gentle breeze plays with the falling leaves, adding a flair of vibrant oranges, yellows, and reds to the scenery. A wholesome atmosphere prevails as the city prepares for the coming harvest festival.Temperature
A mild shift in the average high-temperature occurs in September, reducing from a warm 76.3°F (24.6°C) in August to an agreeable 69.8°F (21°C). In Mequon, the average temperature during the nights of September drops to a moderate 56.5°F (13.6°C).Humidity
The average relative humidity in September is 78%.Rainfall
In Mequon, during September, the rain falls for 12.4 days and regularly aggregates up to 1.97" (50mm) of precipitation. In Mequon, Wisconsin, during the entire year, the rain falls for 136.6 days and collects up to 21.69" (551mm) of precipitation.Snowfall
In Mequon, snow does not fall in May through September.Daylight
In Mequon, the average length of the day in September is 12h and 29min.On the first day of September in Mequon, sunrise is at 6:17 am and sunset at 7:26 pm. On the last day of the month, sunrise is at 6:49 am and sunset at 6:34 pm CDT.
Sunshine
The average sunshine in September in Mequon is 9.2h.UV index
In Mequon, Wisconsin, the average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a medium health hazard from unsafe exposure to UV radiation for average individuals.Note: The UV index of 4 during September translates into the following guidance:
Undertake precautions - Obligation exists to protect against skin and eye damage. It's crucial to reduce time in the direct Sun around mid-day due to the intense solar radiation. A wide-brim hat offers excellent sun protection for the eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Mequon, WI
- Average high temperature in September: 69.8°F
The warmest month (with the highest average high temperature) is July (77°F).
The month with the lowest average high temperature is January (25.9°F).
- Average low temperature in September: 56.5°F
The month with the highest average low temperature is July (64°F).
The coldest month (with the lowest average low temperature) is January (16.2°F).
Average pressure in September
Mequon, WI
- Average pressure in September: 30.03"Hg
The months with the highest atmospheric pressure are January, February and March (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Mequon, WI
- Average wind speed in September: 8.6mph
The windiest month (with the highest average wind speed) is January (11.7mph).
The calmest month (with the lowest average wind speed) is July (7.3mph).
Average humidity in September
Mequon, WI
- Average humidity in September: 78%
The month with the highest relative humidity is January (86%).
The months with the lowest relative humidity are October and November (76%).
Average rainfall in September
Mequon, WI
- Average rainfall in September: 1.97"
The wettest month (with the highest rainfall) is July (2.8").
The driest months (with the least rainfall) are February and December (0.94").
Average rainfall days in September
Mequon, WI
- Average rainfall days in September: 12.4 days
The month with the highest number of rainy days is July (15.7 days).
The month with the least rainy days is February (4.3 days).
Average snowfall in September
Mequon, WI
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.76").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Mequon, WI
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (12.2 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
Mequon, WI
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- Average sunshine in September: 9h and 12min
The months with the most sunshine are July and August (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 3h and 36min).
Average sunshine days in September
Mequon, WI
- Average sunshine days in September: 15 days
The month with the most sunshine days is December (16.8 days).
The month with the least sunshine days is July (11.9 days).
Average UV index in September
Mequon, WI
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Mequon, WI
- Average cloud cover in September: 29
The month with the most cloud cover is January (Cloud cover 62).
The months with the least cloud cover are July and August (Cloud cover 28).
Average visibility in September
Mequon, WI
- 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).
