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
A mild shift in the average high-temperature occurs in September, reducing from a warm 78.1°F (25.6°C) in August to a pleasant 71.6°F (22°C). Winnetka's temperature tends to fall to an average low of 60.3°F (15.7°C) during the nights of September.Humidity
The average relative humidity in September is 74%.Rainfall
In Winnetka, during September, the rain falls for 14.8 days and regularly aggregates up to 2.87" (73mm) of precipitation. Throughout the year, in Winnetka, there are 164.7 rainfall days, and 35.28" (896mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall in Winnetka.Daylight
The average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 6:17 am and sunset at 7:24 pm. On the last day of September, in Winnetka, Illinois, sunrise is at 6:47 am and sunset at 6:33 pm CDT.
Sunshine
The average sunshine in September is 9h.UV index
In September, the average daily maximum UV index in Winnetka is 4. A UV Index estimate of 3 to 5 represents a moderate threat to health from unsafe exposure to UV radiation for ordinary individuals.Note: In September, the maximum UV index of 4 transforms into these recommendations:
Adopt protective measures - It is advised to guard against sun damage. To protect against the Sun's most potent rays, avoid direct exposure around midday. For minimizing sun-related eye damage, always choose sunglasses with UVA and UVB coverage.
Frequently asked questions
What is the temperature in September in Winnetka?
What is the average humidity in September in Winnetka?
How much does it rain in Winnetka in September?
When it does not snow in Winnetka?
Does it snow in Winnetka in September?
How many hours of daylight does Winnetka have in September?
When are sunrise and sunset in September in Winnetka?
How many hours of sunshine does Winnetka have in September?
What is the UV index intensity in September in Winnetka?
Average temperature in September
Winnetka, IL
- Average high temperature in September: 71.6°F
The warmest month (with the highest average high temperature) is July (79.2°F).
The month with the lowest average high temperature is January (28.8°F).
- Average low temperature in September: 60.3°F
The month with the highest average low temperature is July (67.1°F).
The coldest month (with the lowest average low temperature) is January (18.9°F).
Average pressure in September
Winnetka, IL
- 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 (29.92"Hg).
Average wind speed in September
Winnetka, IL
- Average wind speed in September: 8.6mph
The windiest month (with the highest average wind speed) is January (11.5mph).
The calmest month (with the lowest average wind speed) is August (7.1mph).
Average humidity in September
Winnetka, IL
- Average humidity in September: 74%
The month with the highest relative humidity is January (82%).
The month with the lowest relative humidity is October (73%).
Average rainfall in September
Winnetka, IL
- Average rainfall in September: 2.87"
The wettest months (with the highest rainfall) are May and June (4.57").
The driest month (with the least rainfall) is December (1.65").
Average rainfall days in September
Winnetka, IL
- Average rainfall days in September: 14.8 days
The month with the highest number of rainy days is May (19.1 days).
The month with the least rainy days is February (6.1 days).
Average snowfall in September
Winnetka, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (4.84").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Winnetka, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (13.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Winnetka, IL
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in September: 9h and 0min
The months with the most sunshine are July and August (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in September
Winnetka, IL
- Average sunshine days in September: 11.7 days
The month with the most sunshine days is November (15.5 days).
The month with the least sunshine days is June (9.2 days).
Average UV index in September
Winnetka, IL
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Winnetka, IL
- Average cloud cover in September: 30
The month with the most cloud cover is January (Cloud cover 61).
The months with the least cloud cover are July and August (Cloud cover 28).
Average visibility in September
Winnetka, IL
- 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).
Winnetka, Illinois, USA
Weather forecast for your location
2. Allow the app to use your location
