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
With the arrival of September, Round Lake experiences a modest decline in average high-temperatures, transitioning from a moderately hot 78.6°F (25.9°C) in August to a pleasant 72.3°F (22.4°C). Round Lake records a mean low-temperature of 57°F (13.9°C) in September.Humidity
In September, the average relative humidity is 77%.Rainfall
In September, in Round Lake, the rain falls for 11.9 days. Throughout September, 1.57" (40mm) of precipitation is accumulated. Throughout the year, in Round Lake, there are 142.3 rainfall days, and 21.97" (558mm) of precipitation is accumulated.Snowfall
In Round Lake, Illinois, snow does not fall in June through September.Daylight
In Round Lake, 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, the average sunshine in September is 8.9h.UV index
In Round Lake, the average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a medium health hazard from unprotected exposure to Sun's UV rays for the ordinary person.Note: The maximum UV index, 4 during September, leads to the following recommendations:
Exercise caution. The susceptibility of light skin individuals to burns is less than 30 minutes. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. Consider a wide-brim hat essential for effective sun defense covering your face, neck, and eyes.
Frequently asked questions
What is the usual temperature for Round Lake in September?
What is the average humidity in September in Round Lake?
How much does it rain in Round Lake in September?
When it does not snow in Round Lake?
Does it snow in Round Lake in September?
What is the average length of the day in September in Round Lake?
When are sunrise and sunset in September in Round Lake?
How many hours of sunshine does Round Lake have in September?
What is the UV index reading in September in Round Lake?
Average temperature in September
Round Lake, 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, 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, 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, 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, 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, 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, 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, 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, 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, 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, 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, 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, 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, Illinois, USA
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