September weather forecast
Delavan, IL

Share

Weather in September

September, the first month of the autumn in Delavan, is also a moderately hot month, with an average temperature varying between 57.9°F (14.4°C) and 76.5°F (24.7°C).

Temperature

September welcomes an average high-temperature of a still warm 76.5°F (24.7°C), not much different from the preceding month. Delavan experiences a mean low-temperature of 57.9°F (14.4°C) during September.

Humidity

In September, the average relative humidity is 76%.

Rainfall

In Delavan, Illinois, in September, it is raining for 10.3 days, with typically 1.57" (40mm) of accumulated precipitation. In Delavan, during the entire year, the rain falls for 131.4 days and collects up to 20.08" (510mm) of precipitation.

Snowfall

In Delavan, snow does not fall in May through October.

Daylight

In Delavan, the average length of the day in September is 12h and 27min.
On the first day of the month, sunrise is at 6:26 am and sunset at 7:29 pm. On the last day of September, sunrise is at 6:54 am and sunset at 6:41 pm CDT.

Sunshine

In September, the average sunshine is 9.1h.

UV index

In Delavan, the average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a medium vulnerability from unprotected exposure to Sun's UV rays for average individuals.
Note: In September, a daily UV index of 5 turns into the following recommendations:
Take heed. Individuals of lighter complexion can be burned in less than half an hour. Solar radiation peaks around mid-day, so it's wise to limit exposure to the Sun at this time. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear.
Updated: Jul 30, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the average September temperature?

The high-temperature, in September, in Delavan, records 76.5°F (24.7°C), while the low-temperature is 57.9°F (14.4°C). The average heat index (a.k.a. 'real feel', 'feels like'), which takes the relative humidity and factors it into the air temperature reading, in August is evaluated at 87.8°F (31°C).

What is the average humidity in September?

In Delavan, the average relative humidity in September is 76%.

How much does it rain in September?

In Delavan, in September, it is raining for 10.3 days, with typically 1.57" (40mm) of accumulated precipitation.

When it does not snow?

In Delavan, snow does not fall in May through October.

How many hours of daylight does Delavan have in September?

The average day length in September is 12h and 27min.

When is the sunrise / sunset in September?

In September, on the first day of the month, sunrise is at 6:26 am and sunset at 7:29 pm. On the last day of the month, sunrise is at 6:54 am and sunset at 6:41 pm CDT.

How many hours of sunshine does Delavan have in September?

In September, the average sunshine duration in Delavan is 9.1h.

What is the UV index intensity in September?

The average daily maximum UV index in September is 5. A UV Index estimate of 3 to 5 represents a medium hazard to health 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
Delavan, IL

Average temperature in September - Delavan, IL
  • Average high temperature in September: 76.5°F

The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (31.5°F).

  • Average low temperature in September: 57.9°F

The month with the highest average low temperature is July (65.3°F).
The coldest month (with the lowest average low temperature) is January (19.8°F).

Average pressure in September
Delavan, IL

Average pressure in September - Delavan, IL
  • Average pressure in September: 30.03"Hg

The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).

Average wind speed in September
Delavan, IL

Average wind speed in September - Delavan, IL
  • Average wind speed in September: 7.5mph

The windiest month (with the highest average wind speed) is April (10.6mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).

Average humidity in September
Delavan, IL

Average humidity in September - Delavan, 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
Delavan, IL

Average rainfall in September - Delavan, IL
  • Average rainfall in September: 1.57"

The wettest month (with the highest rainfall) is May (2.83").
The driest month (with the least rainfall) is February (1.02").

Average rainfall days in September
Delavan, IL

Average rainfall days in September - Delavan, IL
  • Average rainfall days in September: 10.3 days

The month with the highest number of rainy days is May (17.7 days).
The month with the least rainy days is February (5.1 days).

Average snowfall in September
Delavan, IL

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

The month with the highest snowfall is January (2.87").
The months with the least snowfall are May, June, July, August, September and October (0").

Average snowfall days in September
Delavan, IL

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

The month with the highest number of snowfall days is January (8.4 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
Delavan, IL

Average daylight in September / Average sunshine in September - Delavan, IL
  • Average daylight in September: 12h and 2min

The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).

  • Average sunshine in September: 9h and 1min

The month with the most sunshine is June (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).

Average sunshine days in September
Delavan, IL

Average sunshine days in September - Delavan, IL
  • Average sunshine days in September: 18.8 days

The month with the most sunshine days is November (20 days).
The month with the least sunshine days is May (11.8 days).

Average UV index in September
Delavan, IL

Average UV index in September - Delavan, IL
  • Average UV index in September: 5

The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).

Average cloud cover in September
Delavan, IL

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

The month with the most cloud cover is January (Cloud cover 57).
The month with the least cloud cover is September (Cloud cover 30).

Average visibility in September
Delavan, IL

Average visibility in September - Delavan, 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).

Delavan, Illinois, USA

Weather forecast for your location

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