September weather forecastPontiac, IL
September
Weather in September
September, the first month of the autumn in Pontiac, is also a moderately hot month, with an average temperature ranging between min 57°F (13.9°C) and max 75.6°F (24.2°C).Temperature
The onset of September notes an average high-temperature of a still moderately hot 75.6°F (24.2°C), subtly shifted from August's 80.1°F (26.7°C). An average temperature of 57°F (13.9°C) is recorded in Pontiac during the nights in September.Humidity
The average relative humidity in September is 76%.Rainfall
In Pontiac, during September, the rain falls for 10.1 days and regularly aggregates up to 1.06" (27mm) of precipitation. In Pontiac, during the entire year, the rain falls for 125.3 days and collects up to 15.71" (399mm) of precipitation.Snowfall
In Pontiac, snow does not fall in May through September.Daylight
In Pontiac, 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 8.9h.UV index
In September, the average daily maximum UV index is 4. A UV Index of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV rays for the ordinary person.Note: In September, the maximum UV index of 4 suggests these recommendations:
Exercise prevention - Protecting skin and eyes from harm is required. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. For effective sun eye protection, rely on sunglasses certified for UVA and UVB resistance.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Pontiac, IL
- Average high temperature in September: 75.6°F
The warmest month (with the highest average high temperature) is July (81°F).
The month with the lowest average high temperature is January (30.2°F).
- Average low temperature in September: 57°F
The month with the highest average low temperature is July (64.6°F).
The coldest month (with the lowest average low temperature) is January (18.5°F).
Average pressure in September
Pontiac, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Pontiac, IL
- Average wind speed in September: 7.5mph
The windiest month (with the highest average wind speed) is January (10.7mph).
The calmest month (with the lowest average wind speed) is August (6.3mph).
Average humidity in September
Pontiac, 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
Pontiac, IL
- Average rainfall in September: 1.06"
The wettest month (with the highest rainfall) is May (2.44").
The driest months (with the least rainfall) are January and February (0.71").
Average rainfall days in September
Pontiac, IL
- Average rainfall days in September: 10.1 days
The month with the highest number of rainy days is May (16.8 days).
The month with the least rainy days is January (4.3 days).
Average snowfall in September
Pontiac, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (1.73").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Pontiac, 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
Pontiac, 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: 8h and 54min
The months with the most sunshine are June and August (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days in September
Pontiac, IL
- Average sunshine days in September: 17.8 days
The month with the most sunshine days is November (20.5 days).
The month with the least sunshine days is July (11.3 days).
Average UV index in September
Pontiac, 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 December (UV index 1).
Average cloud cover in September
Pontiac, IL
- Average cloud cover in September: 32
The month with the most cloud cover is January (Cloud cover 59).
The month with the least cloud cover is September (Cloud cover 32).
Average visibility in September
Pontiac, 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).
