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 arrival of September corresponds with a minor reduction in the average high-temperature, down from August's warm 84.7°F (29.3°C) to a still moderately hot 79.3°F (26.3°C). During September, the average low-temperature is a refreshing 59.9°F (15.5°C).Humidity
The average relative humidity in September is 74%.Rainfall
In Granite City, during September, the rain falls for 13.5 days and regularly aggregates up to 2.28" (58mm) of precipitation. Throughout the year, there are 159.5 rainfall days, and 36.06" (916mm) of precipitation is accumulated.Snowfall
In Granite City, snow does not fall in April through October.Daylight
In Granite City, the average length of the day in September is 12h and 25min.On the first day of September, sunrise is at 6:30 am and sunset at 7:30 pm. On the last day of the month, sunrise is at 6:56 am and sunset at 6:44 pm CDT.
Sunshine
In Granite City, the average sunshine in September is 9.5h.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 ordinary individuals.Note: In September, an average UV index of 5 transforms into the following instructions:
Take precautions. Light skin individuals may get burned in less than 30 minutes. Direct Sun exposure should be minimized especially during midday when radiation is most intense. Sunglasses providing both UVA and UVB protection are non-negotiable on sunlit days.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are September temperatures in Granite City?
What is the average humidity in September?
How many days does it rain in September?
When it does not snow?
What is the average length of the day in September?
When are sunrise and sunset in September?
How long on average sun shines in September?
What is the UV index intensity in September in Granite City?
Average temperature in September
Granite City, IL
- Average high temperature in September: 79.3°F
The warmest month (with the highest average high temperature) is July (86.2°F).
The month with the lowest average high temperature is January (37.2°F).
- Average low temperature in September: 59.9°F
The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (24.3°F).
Average pressure in September
Granite City, IL
- Average pressure in September: 30.02"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Granite City, IL
- Average wind speed in September: 6.1mph
The windiest month (with the highest average wind speed) is January (9.4mph).
The calmest month (with the lowest average wind speed) is July (5.5mph).
Average humidity in September
Granite City, IL
- Average humidity in September: 74%
The month with the highest relative humidity is May (78%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Granite City, IL
- Average rainfall in September: 2.28"
The wettest month (with the highest rainfall) is May (4.21").
The driest month (with the least rainfall) is February (1.93").
Average rainfall days in September
Granite City, IL
- Average rainfall days in September: 13.5 days
The months with the highest number of rainy days are May and July (17.8 days).
The month with the least rainy days is January (8.4 days).
Average snowfall in September
Granite City, IL
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.4").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Granite City, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (6.3 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
Granite City, IL
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in September: 9h and 3min
The month with the most sunshine is June (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 4h and 36min).
Average sunshine days in September
Granite City, IL
- Average sunshine days in September: 13.9 days
The month with the most sunshine days is December (18 days).
The month with the least sunshine days is June (10.1 days).
Average UV index in September
Granite City, IL
- Average UV index in September: 5
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Granite City, IL
- Average cloud cover in September: 29
The month with the most cloud cover is January (Cloud cover 50).
The months with the least cloud cover are June and August (Cloud cover 28).
Average visibility in September
Granite City, 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).
Granite City, Illinois, USA
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