September weather forecast
Round Lake Beach, IL

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Weather in September

September, the first month of the autumn in Round Lake Beach, is also an agreeable month, with temperature in the range of an average high of 72.3°F (22.4°C) and an average low of 57°F (13.9°C).

Temperature

September signifies a gentle decline in Round Lake Beach's average high-temperature, easing from a warm 78.6°F (25.9°C) in August to an agreeable 72.3°F (22.4°C). Round Lake Beach throughout September, records an average low-temperature of 57°F (13.9°C).

Humidity

In September, the average relative humidity is 77%.

Rainfall

In Round Lake Beach, in September, it is raining for 11.9 days, with typically 1.57" (40mm) of accumulated precipitation. Throughout the year, there are 142.3 rainfall days, and 21.97" (558mm) of precipitation is accumulated.

Snowfall

In Round Lake Beach, snow does not fall in June through September.

Daylight

In Round Lake Beach, 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 7:25 pm. On the last day of September, sunrise is at 6:49 am and sunset at 6:35 pm CDT.

Sunshine

In Round Lake Beach, the average sunshine in September is 8.9h.

UV index

In Round Lake Beach, the average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV radiation for average individuals.
Note: An average UV index of 4 in September transforms into this advice:
Stay alert. Light-skinned people could suffer burns in less than 30 minutes. Avoiding the Sun's peak radiation during midday hours is essential for health and safety. In the presence of strong sunlight, it's crucial to wear sunglasses that ward off UVA and UVB rays.

Frequently asked questions

What is the temperature in September?

In September, the average high-temperature and low-temperature are 72.3°F (22.4°C) and 57°F (13.9°C) respectively.

What is the average humidity in September?

In Round Lake Beach, the average relative humidity in September is 77%.

How many days does it rain in September?

In September, the rain falls for 11.9 days. Throughout September, 1.57" (40mm) of precipitation is accumulated.

When it does not snow?

In Round Lake Beach, Illinois, snow does not fall in June through September.

Does it snow in September?

In Round Lake Beach, in September, it doesn't snow. In October, it regularly snows.

What is the average length of the day in September?

In Round Lake Beach, the average day length in September 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 7:25 pm. On the last day of the month, sunrise is at 6:49 am and sunset at 6:35 pm CDT.

How many hours of sunshine does Round Lake Beach have in September?

In Round Lake Beach, the average sunshine duration in September is 8.9h.

What is the UV index reading in September?

The average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a medium health risk from unprotected exposure to 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
Round Lake Beach, IL

Average temperature in September - Round Lake Beach, IL
  • Average high temperature in September: 72.3°F

The warmest month (with the highest average high temperature) is July (79.9°F).
The month with the lowest average high temperature is January (27.5°F).

  • Average low temperature in September: 57°F

The month with the highest average low temperature is July (64.4°F).
The coldest month (with the lowest average low temperature) is January (16.5°F).

Average pressure in September
Round Lake Beach, IL

Average pressure in September - Round Lake Beach, IL
  • Average pressure in September: 30.03"Hg

The months with the highest atmospheric pressure are January and February (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).

Average wind speed in September
Round Lake Beach, IL

Average wind speed in September - Round Lake Beach, IL
  • Average wind speed in September: 7.5mph

The windiest month (with the highest average wind speed) is January (10.4mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).

Average humidity in September
Round Lake Beach, IL

Average humidity in September - Round Lake Beach, IL
  • Average humidity in September: 77%

The months with the highest relative humidity are January and February (83%).
The month with the lowest relative humidity is October (74%).

Average rainfall in September
Round Lake Beach, IL

Average rainfall in September - Round Lake Beach, IL
  • Average rainfall in September: 1.57"

The wettest month (with the highest rainfall) is April (2.72").
The driest month (with the least rainfall) is December (0.98").

Average rainfall days in September
Round Lake Beach, IL

Average rainfall days in September - Round Lake Beach, IL
  • Average rainfall days in September: 11.9 days

The month with the highest number of rainy days is July (17.5 days).
The month with the least rainy days is February (5 days).

Average snowfall in September
Round Lake Beach, IL

Average snowfall in September - Round Lake Beach, IL
  • Average snowfall in September: 0"

The month with the highest snowfall is January (3.58").
The months with the least snowfall are June, July, August and September (0").

Average snowfall days in September
Round Lake Beach, IL

Average snowfall days in September - Round Lake Beach, IL
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (13.7 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight in September /
Average sunshine in September
Round Lake Beach, IL

Average daylight in September / Average sunshine in September - Round Lake Beach, 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 6min).

  • Average sunshine in September: 8h and 5min

The month with the most sunshine is August (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).

Average sunshine days in September
Round Lake Beach, IL

Average sunshine days in September - Round Lake Beach, IL
  • Average sunshine days in September: 15.1 days

The month with the most sunshine days is November (17.1 days).
The month with the least sunshine days is May (10.8 days).

Average UV index in September
Round Lake Beach, IL

Average UV index in September - Round Lake Beach, IL
  • Average UV index in September: 4

The months with the highest UV index are 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
Round Lake Beach, IL

Average cloud cover in September - Round Lake Beach, IL
  • Average cloud cover in September: 30

The month with the most cloud cover is January (Cloud cover 61).
The months with the least cloud cover are July, August and September (Cloud cover 30).

Average visibility in September
Round Lake Beach, IL

Average visibility in September - Round Lake Beach, IL
  • Average visibility in September: 6mi

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

Round Lake Beach, Illinois, USA

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