September weather forecastIsland Lake, IL
September
Weather in September
The first month of the autumn, September, is also an agreeable month in Island Lake, Illinois, with an average temperature ranging between min 55.8°F (13.2°C) and max 72.5°F (22.5°C).Temperature
A minor decrease in the average high-temperature is observed during September, shifting from a moderately hot 78.4°F (25.8°C) in August to a pleasant 72.5°F (22.5°C). Nighttime temperature dips to a mean of 55.8°F (13.2°C) during September.Humidity
In September, the average relative humidity is 79%.Rainfall
In Island Lake, during September, the rain falls for 12.4 days and regularly aggregates up to 1.69" (43mm) of precipitation. Throughout the year, in Island Lake, there are 151.2 rainfall days, and 24.17" (614mm) of precipitation is accumulated.Snowfall
In Island Lake, Illinois, snow does not fall in June through September.Daylight
In September, the average length of the day in Island Lake is 12h and 28min.On the first day of the month, sunrise is at 6:18 am and sunset at 7:26 pm. On the last day of September, sunrise is at 6:49 am and sunset at 6:35 pm CDT.
Sunshine
In September, the average sunshine in Island Lake is 9h.UV index
In September, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a medium vulnerability from unsafe exposure to UV radiation for ordinary individuals.Note: In September, a daily UV index of 4 turns into the following recommendations:
Undertake precautions - Guarding against sun damage is counselled. Direct exposure to the Sun's intense radiation around midday should be avoided for health reasons. Loose clothes with a tight weave are optimal for safeguarding yourself against the Sun's rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Island Lake, IL
- Average high temperature in September: 72.5°F
The warmest month (with the highest average high temperature) is July (79.9°F).
The month with the lowest average high temperature is January (27°F).
- Average low temperature in September: 55.8°F
The month with the highest average low temperature is July (63.5°F).
The coldest month (with the lowest average low temperature) is January (15.3°F).
Average pressure in September
Island Lake, 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
Island Lake, IL
- Average wind speed in September: 7.2mph
The windiest month (with the highest average wind speed) is January (10mph).
The calmest month (with the lowest average wind speed) is August (6.2mph).
Average humidity in September
Island Lake, IL
- Average humidity in September: 79%
The months with the highest relative humidity are January and February (84%).
The month with the lowest relative humidity is October (75%).
Average rainfall in September
Island Lake, IL
- Average rainfall in September: 1.69"
The wettest month (with the highest rainfall) is June (3.15").
The driest month (with the least rainfall) is December (1.1").
Average rainfall days in September
Island Lake, IL
- Average rainfall days in September: 12.4 days
The month with the highest number of rainy days is July (18.8 days).
The months with the least rainy days are January and February (5.3 days).
Average snowfall in September
Island Lake, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (3.82").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Island Lake, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (13.2 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Island Lake, IL
- Average daylight in September: 12h and 30min
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 6min).
- Average sunshine in September: 9h and 0min
The month with the most sunshine is July (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 36min).
Average sunshine days in September
Island Lake, IL
- Average sunshine days in September: 14.2 days
The month with the most sunshine days is November (16.2 days).
The month with the least sunshine days is June (10 days).
Average UV index in September
Island Lake, IL
- Average UV index in September: 4
The month with the highest UV index is August (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Island Lake, IL
- Average cloud cover in September: 31
The month with the most cloud cover is January (Cloud cover 62).
The months with the least cloud cover are August and September (Cloud cover 31).
Average visibility in September
Island Lake, IL
- 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).
