September weather forecastGerlaw, IL
September
Weather in September
September, the first month of the autumn in Gerlaw, is also a moderately hot month, with an average temperature ranging between max 75.9°F (24.4°C) and min 56.3°F (13.5°C).Temperature
The advent of September observes an average high-temperature of a still moderately hot 75.9°F (24.4°C), nearly identical to August's 81.1°F (27.3°C). In Gerlaw, September nights witness a steady temperature drop to a refreshing 56.3°F (13.5°C).Humidity
In Gerlaw, the average relative humidity in September is 76%.Rainfall
In Gerlaw, Illinois, during September, the rain falls for 11.6 days and regularly aggregates up to 2.4" (61mm) of precipitation. In Gerlaw, during the entire year, the rain falls for 149.4 days and collects up to 30.16" (766mm) of precipitation.Snowfall
In Gerlaw, snow does not fall in May through September.Daylight
In September, the average length of the day in Gerlaw is 12h and 27min.On the first day of the month, sunrise is at 6:29 am and sunset at 7:34 pm. On the last day of September, in Gerlaw, sunrise is at 6:58 am and sunset at 6:45 pm CDT.
Sunshine
In Gerlaw, the average sunshine in September is 9.4h.UV index
In September, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a medium vulnerability from unprotected exposure to Sun's UV rays for the ordinary person.Note: The maximum daily UV index of 4 in September interprets into the following recommendations:
Act with care - Obligation to protect against skin and eye damage is highlighted. The mid-day Sun emits the most powerful UV radiation, so seek shade and minimize exposure. For minimizing sun-related eye damage, always choose sunglasses with UVA and UVB coverage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Gerlaw, IL
- Average high temperature in September: 75.9°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (29.7°F).
- Average low temperature in September: 56.3°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 (17.6°F).
Average pressure in September
Gerlaw, IL
- Average pressure in September: 30.02"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed in September
Gerlaw, IL
- Average wind speed in September: 7.8mph
The windiest month (with the highest average wind speed) is April (10.7mph).
The calmest months (with the lowest average wind speed) are July and August (6.8mph).
Average humidity in September
Gerlaw, IL
- Average humidity in September: 76%
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Gerlaw, IL
- Average rainfall in September: 2.4"
The wettest month (with the highest rainfall) is May (4.25").
The driest month (with the least rainfall) is January (1.46").
Average rainfall days in September
Gerlaw, IL
- Average rainfall days in September: 11.6 days
The month with the highest number of rainy days is May (19 days).
The month with the least rainy days is February (5.8 days).
Average snowfall in September
Gerlaw, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (4.61").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Gerlaw, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (10.9 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
Gerlaw, IL
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in September: 9h and 24min
The month with the most sunshine is June (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days in September
Gerlaw, IL
- Average sunshine days in September: 16.5 days
The month with the most sunshine days is November (18 days).
The month with the least sunshine days is June (9.2 days).
Average UV index in September
Gerlaw, IL
- Average UV index in September: 4
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in September
Gerlaw, IL
- Average cloud cover in September: 30
The month with the most cloud cover is January (Cloud cover 57).
The months with the least cloud cover are August and September (Cloud cover 30).
Average visibility in September
Gerlaw, IL
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, August, September, October, November and December (6mi).
The month with the lowest visibility is July (5mi).
