September weather forecastFort Atkinson, WI
September
Weather in September
As September sets in, Fort Atkinson transitions from summer to fall, and the temperatures become milder. The change in season is palpable as the average maximum temperature drops to 71.8°F (22.1°C). Decreasing daylight hours and a further drop in rainfall to 2.13" (54mm) marks the progressive shift to autumn. The September weather offers comfortable temperatures and fewer rain showers. The month brings a noticeable change in vegetation as leaves change color.Temperature
The shift from August to September includes a small decrease in the average high-temperature, from a moderately hot 77.5°F (25.3°C) to a pleasant 71.8°F (22.1°C). Throughout September, the temperature tends to fall to a consistent average low of 52.3°F (11.3°C).Humidity
In September, the average relative humidity is 81%.Rainfall
In Fort Atkinson, during September, the rain falls for 13.4 days and regularly aggregates up to 2.13" (54mm) of precipitation. In Fort Atkinson, during the entire year, the rain falls for 149.4 days and collects up to 28.82" (732mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
In Fort Atkinson, the average length of the day in September is 12h and 29min.On the first day of September, sunrise is at 6:20 am and sunset at 7:29 pm. On the last day of the month, sunrise is at 6:52 am and sunset at 6:37 pm CDT.
Sunshine
In Fort Atkinson, the average sunshine in September is 8.6h.UV index
In September, the average daily maximum UV index is 4. A UV Index value of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for average individuals.Note: A maximum high UV index of 4 in September translates into the following recommendations:
Be vigilant - Suggestions to stave off sun damage are provided. During midday, the Sun's radiation is strongest, and it's advisable to reduce direct exposure. 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
Average temperature in September
Fort Atkinson, WI
- Average high temperature in September: 71.8°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 (24.3°F).
- Average low temperature in September: 52.3°F
The month with the highest average low temperature is July (61.5°F).
The coldest month (with the lowest average low temperature) is January (12°F).
Average pressure in September
Fort Atkinson, WI
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Fort Atkinson, WI
- Average wind speed in September: 7.3mph
The windiest month (with the highest average wind speed) is April (9.9mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity in September
Fort Atkinson, WI
- Average humidity in September: 81%
The month with the highest relative humidity is January (88%).
The month with the lowest relative humidity is April (76%).
Average rainfall in September
Fort Atkinson, WI
- Average rainfall in September: 2.13"
The wettest month (with the highest rainfall) is June (3.78").
The driest months (with the least rainfall) are January and February (1.42").
Average rainfall days in September
Fort Atkinson, WI
- Average rainfall days in September: 13.4 days
The month with the highest number of rainy days is May (19.6 days).
The month with the least rainy days is February (5 days).
Average snowfall in September
Fort Atkinson, WI
- Average snowfall in September: 0"
The month with the highest snowfall is February (5.39").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Fort Atkinson, WI
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (15.4 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Fort Atkinson, 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 6min).
- Average sunshine in September: 8h and 36min
The month with the most sunshine is July (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 24min).
Average sunshine days in September
Fort Atkinson, WI
- Average sunshine days in September: 14.4 days
The month with the most sunshine days is November (16.1 days).
The months with the least sunshine days are May and June (9.8 days).
Average UV index in September
Fort Atkinson, WI
- Average UV index in September: 4
The month with the highest UV index is June (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Fort Atkinson, WI
- Average cloud cover in September: 35
The month with the most cloud cover is January (Cloud cover 65).
The month with the least cloud cover is August (Cloud cover 34).
Average visibility in September
Fort Atkinson, WI
- Average visibility in September: 5mi
The months with the highest visibility are March, April, May, June, October and November (6mi).
The months with the lowest visibility are January, February, July, August, September and December (5mi).
