September weather forecastBlue Island, IL
September
Weather in September
September, the first month of the autumn in Blue Island, is also a moderately hot month, with temperature in the range of an average low of 59.2°F (15.1°C) and an average high of 73.6°F (23.1°C).Temperature
September ushers in a minute temperature change, with average high-temperatures reducing from August's 79.9°F (26.6°C) to a still moderately hot 73.6°F (23.1°C). In Blue Island, the nighttime temperature averages to a moderate 59.2°F (15.1°C) during September.Humidity
In September, the average relative humidity is 75%.Rainfall
In Blue Island, during September, the rain falls for 13.5 days and regularly aggregates up to 1.97" (50mm) of precipitation. In Blue Island, during the entire year, the rain falls for 147.7 days and collects up to 23.62" (600mm) of precipitation.Snowfall
May through September are months without snowfall.Daylight
In September, the average length of the day is 12h and 28min.On the first day of the month, sunrise is at 6:17 am and sunset at 7:23 pm. On the last day of September, sunrise is at 6:47 am and sunset at 6:33 pm CDT.
Sunshine
The average sunshine in September is 9.1h.UV index
In September, the average daily maximum UV index in Blue Island is 4. A UV Index estimate of 3 to 5 represents a medium vulnerability from unprotected exposure to Sun's UV rays for the average person.Note: The maximum UV index, 4 during September, leads to the following recommendations:
Ensure safety - Recommendations to avert sunburn are presented. Being in direct Sun during midday can be harmful due to intense solar radiation; take precautions. Sun protection is enhanced with clothing that boasts a tight weave yet offers a loose fit.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Blue Island, IL
- Average high temperature in September: 73.6°F
The warmest month (with the highest average high temperature) is July (81°F).
The month with the lowest average high temperature is January (29.5°F).
- Average low temperature in September: 59.2°F
The month with the highest average low temperature is July (66.6°F).
The coldest month (with the lowest average low temperature) is January (18.9°F).
Average pressure in September
Blue Island, 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
Blue Island, IL
- Average wind speed in September: 7.7mph
The windiest month (with the highest average wind speed) is January (10.6mph).
The calmest month (with the lowest average wind speed) is August (6.5mph).
Average humidity in September
Blue Island, IL
- Average humidity in September: 75%
The months with the highest relative humidity are January and February (82%).
The month with the lowest relative humidity is October (72%).
Average rainfall in September
Blue Island, IL
- Average rainfall in September: 1.97"
The wettest month (with the highest rainfall) is May (3.07").
The driest month (with the least rainfall) is December (1.02").
Average rainfall days in September
Blue Island, IL
- Average rainfall days in September: 13.5 days
The month with the highest number of rainy days is July (18 days).
The month with the least rainy days is February (4.9 days).
Average snowfall in September
Blue Island, IL
- Average snowfall in September: 0"
The month with the highest snowfall is February (3.07").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Blue Island, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (11.8 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
Blue Island, 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 12min).
- Average sunshine in September: 9h and 6min
The month with the most sunshine is August (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in September
Blue Island, IL
- Average sunshine days in September: 13 days
The month with the most sunshine days is November (17.5 days).
The month with the least sunshine days is July (9.8 days).
Average UV index in September
Blue Island, 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
Blue Island, IL
- Average cloud cover in September: 30
The month with the most cloud cover is January (Cloud cover 60).
The month with the least cloud cover is August (Cloud cover 28).
Average visibility in September
Blue Island, 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).
