September weather forecastArrowsmith, IL
September
Weather in September
September, the first month of the autumn in Arrowsmith, is still a warm month, with temperature in the range of an average high of 75.9°F (24.4°C) and an average low of 57.9°F (14.4°C).Temperature
Arrowsmith's average high-temperature in September is a still moderately hot 75.9°F (24.4°C), marking an insignificant difference from the 79.9°F (26.6°C) of August. Arrowsmith experiences an average temperature drop to a moderate 57.9°F (14.4°C) during September nights.Humidity
In Arrowsmith, the average relative humidity in September is 76%.Rainfall
In September, the rain falls for 11.6 days. Throughout September, 1.38" (35mm) of precipitation is accumulated. In Arrowsmith, Illinois, during the entire year, the rain falls for 139 days and collects up to 20.83" (529mm) of precipitation.Snowfall
May through October are months without snowfall.Daylight
In Arrowsmith, the average length of the day in September is 12h and 27min.On the first day of the month, sunrise is at 6:22 am and sunset at 7:26 pm. On the last day of September, sunrise is at 6:50 am and sunset at 6:37 pm CDT.
Sunshine
In September, the average sunshine is 9h.UV index
In Arrowsmith, the average daily maximum UV index in September is 5. A UV Index of 3 to 5 symbolizes a medium vulnerability from unsafe exposure to UV radiation for average individuals.Note: The maximum daily UV index of 5 in September converts into the following recommendations:
Heed the precautions - Protecting the skin and eyes from damage is compulsory. Midday Sun has the strongest UV rays, making it crucial to limit exposure and find shade. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Arrowsmith, IL
- Average high temperature in September: 75.9°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 (31.3°F).
- Average low temperature in September: 57.9°F
The month with the highest average low temperature is July (64.9°F).
The coldest month (with the lowest average low temperature) is January (19.6°F).
Average pressure in September
Arrowsmith, 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
Arrowsmith, IL
- Average wind speed in September: 7.6mph
The windiest month (with the highest average wind speed) is January (11mph).
The calmest month (with the lowest average wind speed) is August (6.5mph).
Average humidity in September
Arrowsmith, IL
- Average humidity in September: 76%
The month with the highest relative humidity is July (85%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Arrowsmith, IL
- Average rainfall in September: 1.38"
The wettest month (with the highest rainfall) is May (2.87").
The driest month (with the least rainfall) is December (1.1").
Average rainfall days in September
Arrowsmith, IL
- Average rainfall days in September: 11.6 days
The month with the highest number of rainy days is May (17.5 days).
The month with the least rainy days is January (5.8 days).
Average snowfall in September
Arrowsmith, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.8").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Arrowsmith, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (9.8 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
Arrowsmith, 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: 9h and 0min
The month with the most sunshine is June (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).
Average sunshine days in September
Arrowsmith, IL
- Average sunshine days in September: 16.5 days
The month with the most sunshine days is November (19.6 days).
The month with the least sunshine days is June (10.3 days).
Average UV index in September
Arrowsmith, 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
Arrowsmith, IL
- Average cloud cover in September: 31
The month with the most cloud cover is January (Cloud cover 58).
The month with the least cloud cover is September (Cloud cover 31).
Average visibility in September
Arrowsmith, 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).
