September weather forecastRoberts, IL
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Roberts, Illinois, with an average temperature varying between 75.7°F (24.3°C) and 57.4°F (14.1°C).Temperature
The arrival of September is marked by an average high-temperature of a still warm 75.7°F (24.3°C), bearing a close resemblance to August. Throughout September, Roberts's nights cool down to an average of 57.4°F (14.1°C).Humidity
The average relative humidity in September is 77%.Rainfall
In Roberts, in September, it is raining for 11.7 days, with typically 1.38" (35mm) of accumulated precipitation. Throughout the year, in Roberts, there are 139.8 rainfall days, and 22.05" (560mm) of precipitation is accumulated.Snowfall
May through October are months without snowfall.Daylight
In Roberts, the average length of the day in September is 12h and 27min.On the first day of the month, sunrise is at 6:20 am and sunset at 7:24 pm. On the last day of September, sunrise is at 6:48 am and sunset at 6:35 pm CDT.
Sunshine
In Roberts, the average sunshine in September is 8.7h.UV index
In September, the average daily maximum UV index is 5. A UV Index of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV rays for the average person.Note: A maximum high UV index of 5 in September translates into the following recommendations:
Adopt protective measures - Requirement to safeguard skin and eyes from harm exists. The intensity of the Sun's UV radiation during midday suggests reducing time spent outdoors. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Roberts, 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 (31.5°F).
- Average low temperature in September: 57.4°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 (19.8°F).
Average pressure in September
Roberts, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Roberts, IL
- Average wind speed in September: 7.5mph
The windiest month (with the highest average wind speed) is January (10.8mph).
The calmest months (with the lowest average wind speed) are July and August (6.5mph).
Average humidity in September
Roberts, IL
- Average humidity in September: 77%
The month with the highest relative humidity is July (85%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Roberts, IL
- Average rainfall in September: 1.38"
The wettest month (with the highest rainfall) is May (2.91").
The driest months (with the least rainfall) are February and December (1.14").
Average rainfall days in September
Roberts, IL
- Average rainfall days in September: 11.7 days
The month with the highest number of rainy days is May (17.4 days).
The month with the least rainy days is January (5.8 days).
Average snowfall in September
Roberts, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.83").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Roberts, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (10.4 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
Roberts, 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 42min
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
Roberts, IL
- Average sunshine days in September: 16 days
The month with the most sunshine days is November (19.4 days).
The month with the least sunshine days is July (10.6 days).
Average UV index in September
Roberts, IL
- Average UV index in September: 5
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Roberts, IL
- Average cloud cover in September: 33
The month with the most cloud cover is January (Cloud cover 60).
The months with the least cloud cover are August and September (Cloud cover 33).
Average visibility in September
Roberts, 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).
