September weather forecastAlden, IL
September
Weather in September
September, the first month of the autumn in Alden, is still a pleasant month, with an average temperature varying between 53.6°F (12°C) and 72.1°F (22.3°C).Temperature
As September arrives, Alden's weather displays a minor decrease in high-temperatures, transitioning from August's warm 77.5°F (25.3°C) to a pleasant 72.1°F (22.3°C). In September, the temperature drops to an average of 53.6°F (12°C) at night.Humidity
In September, the average relative humidity is 81%.Rainfall
In September, the rain falls for 12.5 days. Throughout September, 1.65" (42mm) of precipitation is accumulated. Throughout the year, there are 152.8 rainfall days, and 26.46" (672mm) of precipitation is accumulated.Snowfall
In Alden, Illinois, snow does not fall in June through September.Daylight
In September, the average length of the day is 12h and 28min.On the first day of the month, sunrise is at 6:19 am and sunset at 7:27 pm. On the last day of September, sunrise is at 6:50 am and sunset at 6:36 pm CDT.
Sunshine
The average sunshine in September is 8.4h.UV index
In Alden, the average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a medium vulnerability from unsafe exposure to UV radiation for average individuals.Note: A typical high UV index of 4 in September suggests the following recommendations:
Take precautions - Protection against sunburn is recommended. Sun's radiation is most powerful around mid-day, so it's best to limit outdoor activities during this time. For holistic sun protection encompassing the eyes, ears, face, and neck, a wide-brim hat is key.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Alden, IL
- Average high temperature in September: 72.1°F
The warmest month (with the highest average high temperature) is July (79.3°F).
The month with the lowest average high temperature is January (25.3°F).
- Average low temperature in September: 53.6°F
The month with the highest average low temperature is July (62.6°F).
The coldest month (with the lowest average low temperature) is January (13.3°F).
Average pressure in September
Alden, 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
Alden, IL
- Average wind speed in September: 7.1mph
The windiest month (with the highest average wind speed) is April (9.9mph).
The calmest month (with the lowest average wind speed) is August (6.2mph).
Average humidity in September
Alden, IL
- Average humidity in September: 81%
The month with the highest relative humidity is January (87%).
The months with the lowest relative humidity are April and October (77%).
Average rainfall in September
Alden, IL
- Average rainfall in September: 1.65"
The wettest month (with the highest rainfall) is June (3.58").
The driest month (with the least rainfall) is December (1.3").
Average rainfall days in September
Alden, IL
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is May (18.8 days).
The month with the least rainy days is January (4.9 days).
Average snowfall in September
Alden, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (4.41").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Alden, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (14.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Alden, 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 6min).
- Average sunshine in September: 8h and 24min
The month with the most sunshine is July (Average sunshine: 9h and 36min).
The month with the least sunshine is January (Average sunshine: 3h and 30min).
Average sunshine days in September
Alden, IL
- Average sunshine days in September: 15 days
The month with the most sunshine days is November (16.3 days).
The month with the least sunshine days is May (9.7 days).
Average UV index in September
Alden, IL
- Average UV index in September: 4
The months with the highest UV index are May, June, July and August (UV index 5).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Alden, IL
- Average cloud cover in September: 35
The month with the most cloud cover is January (Cloud cover 64).
The month with the least cloud cover is September (Cloud cover 35).
Average visibility in September
Alden, IL
- Average visibility in September: 5mi
The months with the highest visibility are March, April, May, June, October and November (6mi).
The months with the lowest visibility are January, February, July, August, September and December (5mi).
