Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
The arrival of September is marked by a minor reduction in average high-temperature, sliding from a warm 78.6°F (25.9°C) in August to an agreeable 72.3°F (22.4°C). An average minimum temperature of 57°F (13.9°C) marks the month of September.Humidity
In September, the average relative humidity in Round Lake Park is 77%.Rainfall
In Round Lake Park, in September, it is raining for 11.9 days, with typically 1.57" (40mm) of accumulated precipitation. In Round Lake Park, during the entire year, the rain falls for 142.3 days and collects up to 21.97" (558mm) of precipitation.Snowfall
June through September are months without snowfall in Round Lake Park.Daylight
The average length of the day in September in Round Lake Park 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 6:34 pm CDT.
Sunshine
In Round Lake Park, the average sunshine in September is 8.9h.UV index
In September, the average daily maximum UV index in Round Lake Park is 4. A UV Index reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV radiation for ordinary individuals.Note: In September, the maximum UV index of 4 translates into these guidelines:
Act with care - Obligation to protect against skin and eye damage is highlighted. The intensity of the Sun's UV radiation during midday suggests reducing time spent outdoors. For excellent sun protection for the eyes, ears, face, and neck, consider a wide-brim hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in Round Lake Park in September?
What is the average humidity in September in Round Lake Park?
How many days does it rain in September in Round Lake Park?
When it does not snow in Round Lake Park?
Does it snow in Round Lake Park in September?
How many hours of daylight does Round Lake Park have in September?
When are sunrise and sunset in September in Round Lake Park?
How many hours of sunshine does Round Lake Park have in September?
How high is the UV index in September in Round Lake Park?
Average temperature in September
Round Lake Park, 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 Park, 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 Park, 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 Park, 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 Park, 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 Park, 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 Park, 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 Park, 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 Park, 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 Park, 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 Park, 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 Park, 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 Park, 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 Park, Illinois, USA
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