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
The commencement of September includes a gentle temperature shift, with the average high-temperature dropping a bit from 79.3°F (26.3°C) in August to a still moderately hot 73.9°F (23.3°C). Sterling observes an average low-temperature of 55.2°F (12.9°C) during September.Humidity
In Sterling, Illinois, the average relative humidity in September is 78%.Rainfall
In September, in Sterling, the rain falls for 9.7 days. Throughout September, 1.26" (32mm) of precipitation is accumulated. Throughout the year, there are 130.2 rainfall days, and 17.36" (441mm) of precipitation is accumulated.Snowfall
May through September are months without snowfall.Daylight
In Sterling, Illinois, the average length of the day in September is 12h and 28min.On the first day of September in Sterling, Illinois, sunrise is at 6:25 am and sunset at 7:31 pm. On the last day of the month, sunrise is at 6:55 am and sunset at 6:41 pm CDT.
Sunshine
The average sunshine in September in Sterling is 9.1h.UV index
In Sterling, the average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a medium vulnerability from unsafe exposure to UV radiation for average individuals.Note: In September, the UV index of 4 transforms into the following advice:
Be vigilant - Preventing sunburn is recommended. It's recommended to limit sun exposure when its radiation is at its peak during midday. Protect your eyes, ears, face, and neck from the Sun by wearing a wide-brimmed hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in Sterling in September?
What is the average humidity in September in Sterling?
How much does it rain in Sterling in September?
When it does not snow in Sterling?
Does it snow in Sterling in September?
What is the average length of the day in September in Sterling?
When is the sunrise / sunset in September in Sterling?
How long on average sun shines in September in Sterling?
What is the UV index reading in September in Sterling?
Average temperature in September
Sterling, IL
- Average high temperature in September: 73.9°F
The warmest month (with the highest average high temperature) is July (80.2°F).
The month with the lowest average high temperature is January (27.7°F).
- Average low temperature in September: 55.2°F
The month with the highest average low temperature is July (63.9°F).
The coldest month (with the lowest average low temperature) is January (14.9°F).
Average pressure in September
Sterling, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Sterling, IL
- Average wind speed in September: 7.6mph
The windiest month (with the highest average wind speed) is April (10.4mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity in September
Sterling, IL
- Average humidity in September: 78%
The months with the highest relative humidity are January and July (85%).
The month with the lowest relative humidity is October (73%).
Average rainfall in September
Sterling, IL
- Average rainfall in September: 1.26"
The wettest month (with the highest rainfall) is May (2.83").
The driest months (with the least rainfall) are January and February (0.75").
Average rainfall days in September
Sterling, IL
- Average rainfall days in September: 9.7 days
The month with the highest number of rainy days is May (17.3 days).
The month with the least rainy days is January (4.8 days).
Average snowfall in September
Sterling, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.56").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Sterling, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (10.2 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
Sterling, 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 1min
The month with the most sunshine is July (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days in September
Sterling, IL
- Average sunshine days in September: 18.4 days
The months with the most sunshine days are November and December (18.8 days).
The month with the least sunshine days is June (11.3 days).
Average UV index in September
Sterling, IL
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Sterling, IL
- Average cloud cover in September: 31
The month with the most cloud cover is January (Cloud cover 60).
The month with the least cloud cover is September (Cloud cover 31).
Average visibility in September
Sterling, 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).
Sterling, Illinois, USA
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