September weather forecast
Lyons, IL

Share

Weather in September

September, the first month of the autumn in Lyons, is also an agreeable month, with an average temperature varying between 59.5°F (15.3°C) and 72.9°F (22.7°C).

Temperature

As September arrives, Lyons's weather displays a minor decrease in high-temperatures, transitioning from August's moderately hot 79.3°F (26.3°C) to a pleasant 72.9°F (22.7°C). An average nighttime temperature of 59.5°F (15.3°C) is witnessed throughout September.

Humidity

The average relative humidity in September in Lyons is 74%.

Rainfall

In September, the rain falls for 7.5 days. Throughout September, 0.51" (13mm) of precipitation is accumulated. In Lyons, during the entire year, the rain falls for 92 days and collects up to 7.4" (188mm) of precipitation.

Snowfall

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

Daylight

In September, the average length of the day is 12h and 28min.
On the first day of the month, sunrise is at 6:17 am and sunset at 7:24 pm. On the last day of September, sunrise is at 6:47 am and sunset at 6:34 pm CDT.

Sunshine

In Lyons, the average sunshine in September is 9.1h.

UV index

The average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a medium health hazard from unsafe exposure to UV radiation for the ordinary person.
Note: In September, a daily maximum UV index of 4 leads to the following instructions:
Adopt protective measures - Suggestions to resist sunburn are offered. Avoiding the Sun's peak radiation during midday hours is essential for health and safety. Sun protection is enhanced with clothing that boasts a tight weave yet offers a loose fit.
Updated: Jul 25, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What are the temperatures in September?

An average high-temperature, in September, in Lyons, is 72.9°F (22.7°C) and the average low-temperature is 59.5°F (15.3°C).

What is the average humidity in September?

In September, the average relative humidity is 74%.

How much does it rain in September?

In Lyons, in September, it is raining for 7.5 days, with typically 0.51" (13mm) of accumulated precipitation.

When it does not snow?

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

Does it snow in September?

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

How many hours of daylight does Lyons have in September?

In Lyons, the average day length in September is 12h and 28min.

What time are sunrise and sunset in September?

In September, on the first day of the month, sunrise is at 6:17 am and sunset at 7:24 pm. On the last day of the month, sunrise is at 6:47 am and sunset at 6:34 pm CDT.

How long on average sun shines in September?

In September, the average sunshine duration is 9.1h.

How high is the UV index in September?

In Lyons, Illinois, the average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a moderate vulnerability from exposure to the Sun's UV radiation.
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
Lyons, IL

Average temperature in September - Lyons, IL
  • Average high temperature in September: 72.9°F

The warmest month (with the highest average high temperature) is July (80.4°F).
The month with the lowest average high temperature is January (29.1°F).

  • Average low temperature in September: 59.5°F

The month with the highest average low temperature is July (67.1°F).
The coldest month (with the lowest average low temperature) is January (19.2°F).

Average pressure in September
Lyons, IL

Average pressure in September - Lyons, 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
Lyons, IL

Average wind speed in September - Lyons, IL
  • Average wind speed in September: 8.1mph

The windiest month (with the highest average wind speed) is January (10.9mph).
The calmest month (with the lowest average wind speed) is August (6.8mph).

Average humidity in September
Lyons, IL

Average humidity in September - Lyons, IL
  • Average humidity in September: 74%

The months with the highest relative humidity are January and February (82%).
The month with the lowest relative humidity is October (72%).

Average rainfall in September
Lyons, IL

Average rainfall in September - Lyons, IL
  • Average rainfall in September: 0.51"

The wettest month (with the highest rainfall) is May (1.1").
The driest months (with the least rainfall) are February, March, November and December (0.39").

Average rainfall days in September
Lyons, IL

Average rainfall days in September - Lyons, IL
  • Average rainfall days in September: 7.5 days

The month with the highest number of rainy days is June (11.7 days).
The month with the least rainy days is January (3.1 days).

Average snowfall in September
Lyons, IL

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

The month with the highest snowfall is February (1.38").
The months with the least snowfall are May, June, July, August and September (0").

Average snowfall days in September
Lyons, IL

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

The month with the highest number of snowfall days is February (7.3 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
Lyons, IL

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

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 1min

The month with the most sunshine is August (Average sunshine: 10h and 36min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).

Average sunshine days in September
Lyons, IL

Average sunshine days in September - Lyons, IL
  • Average sunshine days in September: 19.9 days

The month with the most sunshine days is December (23.7 days).
The month with the least sunshine days is June (14.3 days).

Average UV index in September
Lyons, IL

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

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

Average cloud cover in September
Lyons, IL

Average cloud cover in September - Lyons, IL
  • Average cloud cover in September: 30

The month with the most cloud cover is January (Cloud cover 61).
The month with the least cloud cover is August (Cloud cover 27).

Average visibility in September
Lyons, IL

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

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

Lyons, Illinois, USA

Weather forecast for your location

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