September weather forecast
Mokena, IL

Share

Weather in September

September, the first month of the autumn in Mokena, is still a warm month, with an average temperature fluctuating between 57°F (13.9°C) and 74.3°F (23.5°C).

Temperature

In September, the average high-temperature marginally drops from 80.2°F (26.8°C) in August to a still warm 74.3°F (23.5°C). An average low-temperature of 57°F (13.9°C) is observed during September nights.

Humidity

In Mokena, the average relative humidity in September is 77%.

Rainfall

In Mokena, in September, during 13.2 rainfall days, 2.52" (64mm) of precipitation is typically accumulated. Throughout the year, there are 149.8 rainfall days, and 31.26" (794mm) of precipitation is accumulated.

Snowfall

In Mokena, snow does not fall in May through September.

Daylight

In Mokena, the average length of the day in September is 12h and 28min.
On the first day of the month, sunrise is at 6:18 am and sunset at 7:24 pm. On the last day of September, sunrise is at 6:48 am and sunset at 6:34 pm CDT.

Sunshine

In Mokena, the average sunshine in September is 8.3h.

UV index

In September, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a medium health hazard from exposure to the Sun's UV radiation for average individuals.
Note: In September, a regular UV index of 4 translates into these guidelines:
Take necessary precautions - Protection from skin and eye injury is mandatory. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. To cut down UV radiation exposure by about half, sport a wide-brim hat.
Updated: Jun 25, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What are September temperatures?

In September, in Mokena, the average high-temperature is 74.3°F (23.5°C), and the average low-temperature is 57°F (13.9°C). In July, the average heat index (a.k.a. 'feels like', 'real feel'), which calculates the temperature value influenced by the moisture in the air, is computed to be 87.8°F (31°C).

What is the average humidity in September?

The average relative humidity in September is 77%.

How many days does it rain in September?

In September, the rain falls for 13.2 days. Throughout September, 2.52" (64mm) of precipitation is accumulated.

When it does not snow in Mokena?

In Mokena, snow does not fall in May through September.

Does it snow in September?

In Mokena, in September, it doesn't snow. In October, it regularly snows.

How many hours of daylight does Mokena have in September?

The average day length in September in Mokena is 12h and 28min.

What time are sunrise and sunset in September?

On the first day of September, sunrise is at 6:18 am and sunset at 7:24 pm. On the last day of the month, sunrise is at 6:48 am and sunset at 6:34 pm CDT.

How long on average sun shines in September?

In Mokena, the average sunshine duration in September is 8.3h.

What is the UV index intensity in September?

The average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a medium hazard to health from 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
Mokena, IL

Average temperature in September - Mokena, IL
  • Average high temperature in September: 74.3°F

The warmest month (with the highest average high temperature) is July (81.7°F).
The month with the lowest average high temperature is January (29.3°F).

  • Average low temperature in September: 57°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 (17.4°F).

Average pressure in September
Mokena, IL

Average pressure in September - Mokena, 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
Mokena, IL

Average wind speed in September - Mokena, IL
  • Average wind speed in September: 7mph

The windiest month (with the highest average wind speed) is January (9.7mph).
The calmest month (with the lowest average wind speed) is August (6mph).

Average humidity in September
Mokena, IL

Average humidity in September - Mokena, IL
  • Average humidity in September: 77%

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

Average rainfall in September
Mokena, IL

Average rainfall in September - Mokena, IL
  • Average rainfall in September: 2.52"

The wettest month (with the highest rainfall) is May (4.21").
The driest months (with the least rainfall) are February and December (1.61").

Average rainfall days in September
Mokena, IL

Average rainfall days in September - Mokena, IL
  • Average rainfall days in September: 13.2 days

The months with the highest number of rainy days are June and July (17.3 days).
The month with the least rainy days is February (5.3 days).

Average snowfall in September
Mokena, IL

Average snowfall in September - Mokena, IL
  • Average snowfall in September: 0"

The month with the highest snowfall is January (4.53").
The months with the least snowfall are May, June, July, August and September (0").

Average snowfall days in September
Mokena, IL

Average snowfall days in September - Mokena, IL
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (12.3 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
Mokena, IL

Average daylight in September / Average sunshine in September - Mokena, 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 2min

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

Average sunshine days in September
Mokena, IL

Average sunshine days in September - Mokena, IL
  • Average sunshine days in September: 15 days

The month with the most sunshine days is November (17.1 days).
The month with the least sunshine days is April (10.7 days).

Average UV index in September
Mokena, IL

Average UV index in September - Mokena, IL
  • Average UV index in September: 4

The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January and December (UV index 1).

Average cloud cover in September
Mokena, IL

Average cloud cover in September - Mokena, IL
  • Average cloud cover in September: 35

The month with the most cloud cover is January (Cloud cover 62).
The month with the least cloud cover is August (Cloud cover 34).

Average visibility in September
Mokena, IL

Average visibility in September - Mokena, IL
  • Average visibility in September: 6mi

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

Mokena, Illinois, USA

Weather forecast for your location

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