September weather forecastRisk, IL
September
Weather in September
The first month of the autumn, September, is still a warm month in Risk, Illinois, with temperature in the range of an average high of 75.7°F (24.3°C) and an average low of 57.2°F (14°C).Temperature
The average high-temperature is a still warm 75.7°F (24.3°C) in September, hardly different from the 79.7°F (26.5°C) recorded in August. During the month of September, an average temperature of 57.2°F (14°C) is noted during the nights.Humidity
The average relative humidity in September is 76%.Rainfall
In Risk, in September, during 10.5 rainfall days, 1.18" (30mm) of precipitation is typically accumulated. In Risk, during the entire year, the rain falls for 130.5 days and collects up to 17.44" (443mm) of precipitation.Snowfall
May through September are months without snowfall.Daylight
In September, the average length of the day is 12h and 27min.On the first day of September, sunrise is at 6:21 am and sunset at 7:25 pm. On the last day of the month, sunrise is at 6:49 am and sunset at 6:36 pm CDT.
Sunshine
In Risk, the average sunshine in September is 8.9h.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 unprotected exposure to Sun's UV rays for ordinary individuals.Note: The UV index of 4 in September translates into these instructions:
Act with care - Obligation to protect against skin and eye damage is highlighted. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. To cut down UV radiation exposure by about half, sport a wide-brim hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Risk, IL
- Average high temperature in September: 75.7°F
The warmest month (with the highest average high temperature) is July (80.8°F).
The month with the lowest average high temperature is January (30.6°F).
- Average low temperature in September: 57.2°F
The month with the highest average low temperature is July (64.6°F).
The coldest month (with the lowest average low temperature) is January (18.5°F).
Average pressure in September
Risk, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Risk, IL
- Average wind speed in September: 7.6mph
The windiest month (with the highest average wind speed) is January (10.8mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity in September
Risk, IL
- Average humidity in September: 76%
The month with the highest relative humidity is July (86%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Risk, IL
- Average rainfall in September: 1.18"
The wettest month (with the highest rainfall) is May (2.56").
The driest month (with the least rainfall) is January (0.79").
Average rainfall days in September
Risk, IL
- Average rainfall days in September: 10.5 days
The month with the highest number of rainy days is May (17 days).
The months with the least rainy days are January and February (5 days).
Average snowfall in September
Risk, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.09").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Risk, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (10.6 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
Risk, IL
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in September: 8h and 54min
The month with the most sunshine is June (Average sunshine: 9h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days in September
Risk, IL
- Average sunshine days in September: 17.2 days
The month with the most sunshine days is November (19.5 days).
The month with the least sunshine days is July (11.4 days).
Average UV index in September
Risk, IL
- Average UV index in September: 4
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Risk, IL
- Average cloud cover in September: 32
The month with the most cloud cover is January (Cloud cover 59).
The month with the least cloud cover is September (Cloud cover 32).
Average visibility in September
Risk, IL
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).





