September weather forecastHarmon, IL
September
Weather in September
September, the first month of the autumn in Harmon, is also a moderately hot month, with temperature in the range of an average low of 55.2°F (12.9°C) and an average high of 73.9°F (23.3°C).Temperature
As August makes way for September, Harmon's average high-temperature eases from 79.3°F (26.3°C) to a still moderately hot 73.9°F (23.3°C). During the nights in September, Harmon observes an average low-temperature of 55.2°F (12.9°C).Humidity
In September, the average relative humidity is 78%.Rainfall
In Harmon, Illinois, in September, during 9.7 rainfall days, 1.26" (32mm) of precipitation is typically accumulated. In Harmon, Illinois, during the entire year, the rain falls for 130.2 days and collects up to 17.36" (441mm) of precipitation.Snowfall
May through September are months without snowfall in Harmon.Daylight
In September, the average length of the day in Harmon is 12h and 28min.On the first day of September, sunrise is at 6:24 am and sunset at 7:31 pm. On the last day of the month, sunrise is at 6:54 am and sunset at 6:41 pm CDT.
Sunshine
In September, the average sunshine in Harmon is 9.1h.UV index
In Harmon, the average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for the average person.Note: The maximum UV index of 4 during September leads to these instructions:
Take precautions. Light skin individuals may get burned in less than 30 minutes. Avoiding direct sunlight during midday hours helps reduce the risk from intense UV radiation. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Harmon, 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
Harmon, 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
Harmon, 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
Harmon, 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
Harmon, 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
Harmon, 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
Harmon, 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
Harmon, 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
Harmon, 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 12min).
- Average sunshine in September: 9h and 6min
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
Harmon, 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
Harmon, 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
Harmon, 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
Harmon, 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).
