September weather forecast
South Chicago Heights, IL

Share

Weather in September

September, the first month of the autumn in South Chicago Heights, is still a warm month, with an average temperature varying between 57.6°F (14.2°C) and 74.5°F (23.6°C).

Temperature

September is characterized by a mild reduction in the average high-temperature, from a moderately hot 80.4°F (26.9°C) in August to a still warm 74.5°F (23.6°C). Nighttime temperature experiences an average drop to a moderate 57.6°F (14.2°C) in September.

Humidity

In South Chicago Heights, Illinois, the average relative humidity in September is 76%.

Rainfall

In South Chicago Heights, in September, during 14.5 rainfall days, 2.56" (65mm) of precipitation is typically accumulated. In South Chicago Heights, during the entire year, the rain falls for 167.4 days and collects up to 35" (889mm) of precipitation.

Snowfall

In South Chicago Heights, snow does not fall in May through September.

Daylight

In South Chicago Heights, the average length of the day in September is 12h and 28min.
On the first day of the month, sunrise is at 6:17 am and sunset at 7:23 pm. On the last day of September, sunrise is at 6:47 am and sunset at 6:33 pm CDT.

Sunshine

In South Chicago Heights, Illinois, the average sunshine in September is 8.5h.

UV index

In September, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a moderate threat to health from unprotected exposure to Sun's UV rays for ordinary individuals.
Note: The maximum daily UV index of 4 in September converts into the following recommendations:
Undertake protective steps - Preventing sun damage is advised. To protect against the Sun's most potent rays, avoid direct exposure around midday. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes.
Updated: Aug 30, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What are September temperatures?

In September, in South Chicago Heights, the average high-temperature is 74.5°F (23.6°C), and the average low-temperature is 57.6°F (14.2°C). The average heat index (a.k.a. 'real feel', 'apparent temperature'), which combines relative humidity and air temperature, in July is evaluated at 89.6°F (32°C).

What is the average humidity in September?

The average relative humidity in September is 76%.

How many days does it rain in September?

In South Chicago Heights, in September, during 14.5 rainfall days, 2.56" (65mm) of precipitation is typically accumulated.

When it does not snow?

In South Chicago Heights, snow does not fall in May through September.

Does it snow in September?

In South Chicago Heights, in September, it doesn't snow. In October, it regularly snows.

What is the average length of the day in September?

The average day length in September in South Chicago Heights is 12h and 28min.

When are sunrise and sunset in September in South Chicago Heights?

On the first day of September, sunrise is at 6:17 am and sunset at 7:23 pm. On the last day of the month, sunrise is at 6:47 am and sunset at 6:33 pm CDT.

How many hours of sunshine does South Chicago Heights have in September?

In South Chicago Heights, the average sunshine duration in September is 8.5h.

What is the UV index intensity in September?

In September, the average daily maximum UV index is 4. A UV Index of 3 to 5 symbolizes a moderate health threat from unsafe exposure to Sun's UV rays.
Average humidity
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
South Chicago Heights, IL

Average temperature in September - South Chicago Heights, IL
  • Average high temperature in September: 74.5°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: 57.6°F

The month with the highest average low temperature is July (65.7°F).
The coldest month (with the lowest average low temperature) is January (18.9°F).

Average pressure in September
South Chicago Heights, IL

Average pressure in September - South Chicago Heights, 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
South Chicago Heights, IL

Average wind speed in September - South Chicago Heights, IL
  • Average wind speed in September: 7.1mph

The windiest month (with the highest average wind speed) is January (10mph).
The calmest month (with the lowest average wind speed) is August (6.2mph).

Average humidity in September
South Chicago Heights, IL

Average humidity in September - South Chicago Heights, IL
  • Average humidity in September: 76%

The month with the highest relative humidity is February (83%).
The month with the lowest relative humidity is October (73%).

Average rainfall in September
South Chicago Heights, IL

Average rainfall in September - South Chicago Heights, IL
  • Average rainfall in September: 2.56"

The wettest month (with the highest rainfall) is May (4.53").
The driest month (with the least rainfall) is November (1.81").

Average rainfall days in September
South Chicago Heights, IL

Average rainfall days in September - South Chicago Heights, IL
  • Average rainfall days in September: 14.5 days

The month with the highest number of rainy days is July (20.1 days).
The month with the least rainy days is February (6.2 days).

Average snowfall in September
South Chicago Heights, IL

Average snowfall in September - South Chicago Heights, IL
  • Average snowfall in September: 0"

The month with the highest snowfall is February (5.35").
The months with the least snowfall are May, June, July, August and September (0").

Average snowfall days in September
South Chicago Heights, IL

Average snowfall days in September - South Chicago Heights, IL
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (13.2 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight in September /
Average sunshine in September
South Chicago Heights, IL

Average daylight in September / Average sunshine in September - South Chicago Heights, IL
  • Average daylight in September: 12h and 3min

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 12min).

  • Average sunshine in September: 8h and 3min

The month with the most sunshine is August (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 36min).

Average sunshine days in September
South Chicago Heights, IL

Average sunshine days in September - South Chicago Heights, IL
  • Average sunshine days in September: 12.7 days

The month with the most sunshine days is November (16.3 days).
The month with the least sunshine days is July (7.8 days).

Average UV index in September
South Chicago Heights, IL

Average UV index in September - South Chicago Heights, 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
South Chicago Heights, IL

Average cloud cover in September - South Chicago Heights, IL
  • Average cloud cover in September: 34

The month with the most cloud cover is January (Cloud cover 62).
The month with the least cloud cover is August (Cloud cover 33).

Average visibility in September
South Chicago Heights, IL

Average visibility in September - South Chicago Heights, IL
  • Average visibility in September: 6mi

The months with the highest visibility are March, April, May, June, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February and July (5mi).

South Chicago Heights, Illinois, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location