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Contents
- Weather in January
- Weather in February
- Weather in March
- Weather in April
- Weather in May
- Weather in June
- Weather in July
- Weather in August
- Weather in September
- Weather in October
- Weather in November
- Weather in December
- Frequently asked questions
- Average temperature
- Average pressure
- Average wind speed
- Average humidity
- Average rainfall
- Average rainfall days
- Average snowfall
- Average snowfall days
- Average daylight
- Average sunshine
- Average sunshine days
- Average UV index
- Average cloud cover
- Average visibility
Weather in January
January, like December, is a freezing cold winter month in Round Lake, Illinois, with an average temperature ranging between min 16.5°F (-8.6°C) and max 27.5°F (-2.5°C). January, recording an average high temperature of 27.5°F (-2.5°C) and a low temperature of 16.5°F (-8.6°C), is Round Lake's coldest month. Weather in January »
Weather in February
February, the last month of the winter in Round Lake, is another freezing cold month, with an average temperature varying between 18.7°F (-7.4°C) and 30.6°F (-0.8°C). The beginning of February reveals an average high-temperature of a still subzero cold 30.6°F (-0.8°C), showing minimal deviation from the previous month. Weather in February »
Weather in March
March, the first month of the spring in Round Lake, is a frosty month, with temperature in the range of an average low of 30.2°F (-1°C) and an average high of 42.8°F (6°C). The arrival of March brings a temperature shift, with the average high-temperature escalating from a freezing cold 30.6°F (-0.8°C) in February to a frosty 42.8°F (6°C). Weather in March »
Weather in April
April is a cool spring month in Round Lake, Illinois, with an average temperature varying between 53.6°F (12°C) and 38.8°F (3.8°C). The shift into April is accompanied by a temperature increase, with the average high-temperature rising from a frosty 42.8°F (6°C) in March to a fresh 53.6°F (12°C). Weather in April »
Weather in May
May, the last month of the spring in Round Lake, is a comfortable month, with an average temperature fluctuating between 49.6°F (9.8°C) and 65.3°F (18.5°C). May witnesses an increase in the average high-temperature, moving from a cool 53.6°F (12°C) in April to a refreshing 65.3°F (18.5°C). Weather in May »
Weather in June
June, the first month of the summer in Round Lake, is a moderately hot month, with temperature in the range of an average low of 58.8°F (14.9°C) and an average high of 74.8°F (23.8°C). An upsurge in temperatures occurs as May gives way to June, with average highs shifting from a comfortable 65.3°F (18.5°C) to a warm 74.8°F (23.8°C). Weather in June »
Weather in July
July, like June, in Round Lake, Illinois, is another warm summer month, with an average temperature ranging between min 64.4°F (18°C) and max 79.9°F (26.6°C). During the warmest month, July, temperatures average a high of 79.9°F (26.6°C) and a low of 64.4°F (18°C). Weather in July »
Weather in August
August, the last month of the summer in Round Lake, is also a moderately hot month, with temperature in the range of an average low of 63.1°F (17.3°C) and an average high of 78.6°F (25.9°C). The average high-temperature for August is a still moderately hot 78.6°F (25.9°C), closely aligning with the temperature of the preceding month. Weather in August »
Weather in September
The first month of the autumn, September, is also an agreeable month in Round Lake, Illinois, with an average temperature ranging between min 57°F (13.9°C) and max 72.3°F (22.4°C). September is characterized by a mild reduction in the average high-temperature, from a moderately hot 78.6°F (25.9°C) in August to a pleasant 72.3°F (22.4°C). Weather in September »
Weather in October
October, like September, is a moderate autumn month in Round Lake, Illinois, with an average temperature ranging between max 59°F (15°C) and min 45.1°F (7.3°C). The average high-temperature decreases in October, shifting from an agreeable 72.3°F (22.4°C) in September to a mild 59°F (15°C). Weather in October »
Weather in November
November, the last month of the autumn in Round Lake, is also a frosty month, with an average temperature ranging between min 32.9°F (0.5°C) and max 45.1°F (7.3°C). The onset of November is marked by a decrease in temperature, transitioning from a refreshing 59°F (15°C) in October to a chilly 45.1°F (7.3°C). Weather in November »
Weather in December
The first month of the winter, December, is also a wintry month in Round Lake, Illinois, with an average temperature ranging between max 33.6°F (0.9°C) and min 23.9°F (-4.5°C). In Round Lake, the beginning of December is marked by a lowered average high-temperature, shifting from November's chilly 45.1°F (7.3°C) to an icy 33.6°F (0.9°C). Weather in December »
Updated: Aug 24, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What part of the year is the coldest?
In Round Lake, the average lowest temperatures are observed in January, with a high of 27.5°F (-2.5°C) and a low of 16.5°F (-8.6°C).
What is the most humid month?
January and February, with an average relative humidity of 83%, are most humid months in Round Lake.
How many days does it rain?
In Round Lake, during the entire year, the rain falls for 142.3 days and collects up to 21.97" (558mm) of precipitation.
When does it snow?
Months with snowfall are January through May, October through December.
When does it snow the most?
The month with the most snowfall is January, when snow falls for 13.7 days and typically aggregates up to 3.58" (91mm) of snow.
How much does it snow?
Throughout the year, there are 49.5 snowfall days, and 13.54" (344mm) of snow is accumulated.
What is the month with the least sunshine?
With an average of 3.7h of sunshine, January has the least sunshine of the year.
When is the lowest UV index?
The months with the lowest UV index in Round Lake are January and December, with an average maximum UV index of 1.
When is Daylight Saving Time (DST)?
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts, and the time zone changes from CST to CDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from CDT to CST.
What is the wettest month in Round Lake?
The month with the most rainfall is April, when the rain falls for 14.8 days and typically aggregates up to 2.72" (69mm) of precipitation.
When it does not snow in Round Lake?
In Round Lake, snow does not fall in June through September.
When are the longest days?
June has the longest days of the year in Round Lake, with an average of 15h and 12min of daylight.
What is the hottest time of year?
July tends to be the warmest month, with temperatures averaging a daily high of 79.9°F (26.6°C) and a low of 64.4°F (18°C).
What is the month with the highest UV index?
The months with the highest UV index are July and August, with an average maximum UV index of 6.
What month has the most sunshine in Round Lake?
August has the most sunshine of the year in Round Lake, with an average of 10.2h of sunshine.
What is the least humid month?
The least humid month in Round Lake is October, with an average relative humidity of 74%.
What is the driest month?
December is the month with the least rainfall. Rain falls for 8.2 days and accumulates 0.98" (25mm) of precipitation.
What is the month with the shortest days?
With an average of 9h and 6min of daylight, December has the shortest days of the year.
Average temperature
Round Lake, IL
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).
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
Round Lake, IL
- Average pressure in January:
30.1"Hg - Average pressure in February:
30.1"Hg - Average pressure in March:
30.09"Hg - Average pressure in April:
29.96"Hg - Average pressure in May:
29.96"Hg - Average pressure in June:
29.92"Hg
- Average pressure in July:
29.97"Hg - Average pressure in August:
29.98"Hg - Average pressure in September:
30.03"Hg - Average pressure in October:
30"Hg - Average pressure in November:
30.09"Hg - Average pressure in December:
30.09"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
Round Lake, IL
- Average wind speed in January:
10.4mph - Average wind speed in February:
10.3mph - Average wind speed in March:
9.8mph - Average wind speed in April:
9.9mph - Average wind speed in May:
8.4mph - Average wind speed in June:
7.4mph
- Average wind speed in July:
6.6mph - Average wind speed in August:
6.4mph - Average wind speed in September:
7.5mph - Average wind speed in October:
9.1mph - Average wind speed in November:
9.8mph - Average wind speed in December:
9.6mph
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
Round Lake, IL
The months with the highest relative humidity are January and February (83%).
The month with the lowest relative humidity is October (74%).
Average rainfall
Round Lake, IL
- Average rainfall in January:
1.14" - Average rainfall in February:
1.22" - Average rainfall in March:
1.18" - Average rainfall in April:
2.72" - Average rainfall in May:
2.44" - Average rainfall in June:
2.6"
- Average rainfall in July:
2.48" - Average rainfall in August:
2.64" - Average rainfall in September:
1.57" - Average rainfall in October:
1.89" - Average rainfall in November:
1.1" - Average rainfall in December:
0.98"
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
Round Lake, IL
- Average rainfall days in January:
5.4 days - Average rainfall days in February:
5 days - Average rainfall days in March:
10.1 days - Average rainfall days in April:
14.8 days - Average rainfall days in May:
17 days - Average rainfall days in June:
15.7 days
- Average rainfall days in July:
17.5 days - Average rainfall days in August:
16 days - Average rainfall days in September:
11.9 days - Average rainfall days in October:
13.2 days - Average rainfall days in November:
7.5 days - Average rainfall days in December:
8.2 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
Round Lake, IL
- Average snowfall in January:
3.58" - Average snowfall in February:
3.54" - Average snowfall in March:
1.22" - Average snowfall in April:
1.61" - Average snowfall in May:
0.04" - Average snowfall in June:
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
Round Lake, IL
- Average snowfall days in January:
13.7 days - Average snowfall days in February:
10.7 days - Average snowfall days in March:
7.1 days - Average snowfall days in April:
2.5 days - Average snowfall days in May:
0.2 days - Average snowfall days in June:
0 days
- Average snowfall days in July:
0 days - Average snowfall days in August:
0 days - Average snowfall days in September:
0 days - Average snowfall days in October:
0.5 days - Average snowfall days in November:
4.4 days - Average snowfall days in December:
10.4 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 / Average sunshine
Round Lake, IL
- Average daylight in January:
9h and 3min - Average daylight in February:
10h and 4min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 2min - Average daylight in May:
14h and 4min - Average daylight in June:
15h and 1min
- Average daylight in July:
14h and 5min - Average daylight in August:
13h and 5min - Average daylight in September:
12h and 3min - Average daylight in October:
11h and 0min - Average daylight in November:
9h and 5min - Average daylight in December:
9h and 1min
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 January:
3h and 4min - Average sunshine in February:
3h and 5min - Average sunshine in March:
5h and 5min - Average sunshine in April:
7h and 4min - Average sunshine in May:
8h and 3min - Average sunshine in June:
9h and 4min
- Average sunshine in July:
10h and 1min - Average sunshine in August:
10h and 1min - Average sunshine in September:
8h and 5min - Average sunshine in October:
5h and 3min - Average sunshine in November:
5h and 0min - Average sunshine in December:
4h and 0min
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
Round Lake, IL
- Average sunshine days in January:
13.7 days - Average sunshine days in February:
12.3 days - Average sunshine days in March:
14.8 days - Average sunshine days in April:
11.6 days - Average sunshine days in May:
10.8 days - Average sunshine days in June:
11.7 days
- Average sunshine days in July:
11.1 days - Average sunshine days in August:
11.7 days - Average sunshine days in September:
15.1 days - Average sunshine days in October:
14.7 days - Average sunshine days in November:
17.1 days - Average sunshine days in December:
15.4 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
Round Lake, IL
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
Round Lake, IL
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
Round Lake, IL
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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