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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, the same as December, in Romeoville, Illinois, is another subzero cold winter month, with an average temperature fluctuating between 17.1°F (-8.3°C) and 28.8°F (-1.8°C). Romeoville's coldest weather arrives in January, when temperatures average a high of 28.8°F (-1.8°C) and a low of 17.1°F (-8.3°C). Weather in January »
Weather in February
February, the last month of the winter in Romeoville, is a cold month, with an average temperature varying between 32.5°F (0.3°C) and 19.9°F (-6.7°C). The onset of February brings with it an average high-temperature of a wintry 32.5°F (0.3°C), showing a negligible variation from the month before. Weather in February »
Weather in March
March, the first month of the spring in Romeoville, is a frosty month, with an average temperature fluctuating between 45.7°F (7.6°C) and 32°F (0°C). The arrival of March brings a change in Romeoville's weather, with average high-temperatures moving from February's cold 32.5°F (0.3°C) to a chilly 45.7°F (7.6°C). Weather in March »
Weather in April
April in Romeoville, Illinois, is a refreshing spring month, with temperature in the range of an average low of 41°F (5°C) and an average high of 57°F (13.9°C). April's onset witnesses a shift in the average high-temperature, moving from a chilly 45.7°F (7.6°C) in March to a moderate 57°F (13.9°C). Weather in April »
Weather in May
The last month of the spring, May, is a pleasant month in Romeoville, Illinois, with an average temperature varying between 69.4°F (20.8°C) and 52.3°F (11.3°C). As May begins, there is an increase in the average high-temperature, moving from a mild 57°F (13.9°C) in April to an agreeable 69.4°F (20.8°C). Weather in May »
Weather in June
The first month of the summer, June, is a moderately hot month in Romeoville, Illinois, with an average temperature varying between 78.6°F (25.9°C) and 61.3°F (16.3°C). Romeoville's transition into June brings a rise in the average high-temperature, moving from an agreeable 69.4°F (20.8°C) in May to a warm 78.6°F (25.9°C). Weather in June »
Weather in July
July, the same as June, is a moderately hot summer month in Romeoville, Illinois, with an average temperature fluctuating between 81.9°F (27.7°C) and 65.7°F (18.7°C). Temperature readings reach their annual highs in July, averaging 81.9°F (27.7°C) and a minimum average of 65.7°F (18.7°C). The heat index value for July is evaluated at a hot 87.8°F (31°C). Weather in July »
Weather in August
The last month of the summer, August, is another warm month in Romeoville, Illinois, with an average temperature ranging between min 63.9°F (17.7°C) and max 80.2°F (26.8°C). August's advent denotes a minor fluctuation in the average high-temperature to a still moderately hot 80.2°F (26.8°C) from July's 81.9°F (27.7°C). Weather in August »
Weather in September
The first month of the autumn, September, is also a moderately hot month in Romeoville, Illinois, with temperature in the range of an average low of 57.4°F (14.1°C) and an average high of 74.3°F (23.5°C). September marks a gentle change in average high-temperature, declining from August's 80.2°F (26.8°C) to a still moderately hot 74.3°F (23.5°C). Weather in September »
Weather in October
October, like September, is another refreshing autumn month in Romeoville, Illinois, with temperature in the range of an average low of 45.5°F (7.5°C) and an average high of 60.6°F (15.9°C). With the onset of October, Romeoville experiences a modest temperature adjustment, with the average high-temperature receding from a warm 74.3°F (23.5°C) in September to a mild 60.6°F (15.9°C). Weather in October »
Weather in November
The last month of the autumn, November, is another chilly month in Romeoville, Illinois, with an average temperature ranging between max 46.6°F (8.1°C) and min 33.4°F (0.8°C). Romeoville's November weather comes with a decrease in average high-temperatures, moving from a moderate 60.6°F (15.9°C) in October to a frosty 46.6°F (8.1°C). Weather in November »
Weather in December
December, the first month of the winter in Romeoville, is also an icy month, with an average temperature ranging between min 24.6°F (-4.1°C) and max 34.7°F (1.5°C). The onset of December is marked by a decrease in temperature, transitioning from a frosty 46.6°F (8.1°C) in November to a wintry 34.7°F (1.5°C). Weather in December »
[Resources]Frequently asked questions
What month is the coldest in Romeoville?
With average temperatures fluctuating between a high of 28.8°F (-1.8°C) and a low of 17.1°F (-8.3°C), January stands out as the coldest month.
What are the most humid months in Romeoville?
January and February, with an average relative humidity of 83%, are most humid months in Romeoville, Illinois.
How many days does it rain in Romeoville?
Throughout the year, in Romeoville, there are 145.4 rainfall days, and 22.83" (580mm) of precipitation is accumulated.
When does it snow in Romeoville?
January through May, October through December are months with snowfall.
When does it snow the most in Romeoville?
January is the month with the most snowfall in Romeoville. Snow falls for 12.1 days and accumulates 3.11" (79mm) of snow.
How many days does it snow in Romeoville?
Throughout the year, there are 44.4 snowfall days, and 11.93" (303mm) of snow is accumulated.
What is the month with the least sunshine in Romeoville?
The month with the least sunshine is January, with an average of 3.8h of sunshine.
When is Daylight Saving Time (DST) in Romeoville?
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts in Romeoville, 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 rainiest month in Romeoville?
May is the month with the most rainfall. Rain falls for 16.4 days and accumulates 2.83" (72mm) of precipitation.
When it does not snow in Romeoville?
June through September are months without snowfall in Romeoville, Illinois.
When are the longest days in Romeoville?
June has the longest days of the year, with an average of 15h and 6min of daylight.
What is the month with the highest UV index in Romeoville?
The months with the highest UV index in Romeoville, Illinois, are June through August, with an average maximum UV index of 6.
What part of the year is the hottest in Romeoville?
In Romeoville, the peak average temperatures are observed in July, with a high of 81.9°F (27.7°C) and a low of 65.7°F (18.7°C).
What is the month with the most sunshine in Romeoville?
The months with the most sunshine in Romeoville, Illinois, are July and August, with an average of 9.9h of sunshine.
What is the least humid month in Romeoville?
With an average relative humidity of 73%, October is the least humid month.
What is the driest month in Romeoville?
December is the month with the least rainfall. Rain falls for 7.1 days and accumulates 1.06" (27mm) of precipitation.
What is the month with the shortest days in Romeoville?
With an average of 9h and 12min of daylight, December has the shortest days of the year.
When is the lowest UV index in Romeoville?
The month with the lowest UV index in Romeoville is December, with an average maximum UV index of 1.
Average temperature
Romeoville, IL
The warmest month (with the highest average high temperature) is July (81.9°F).
The month with the lowest average high temperature is January (28.8°F).
The month with the highest average low temperature is July (65.7°F).
The coldest month (with the lowest average low temperature) is January (17.1°F).
Average pressure
Romeoville, IL
- Average pressure in January:
30.11"Hg - Average pressure in February:
30.1"Hg - Average pressure in March:
30.09"Hg - Average pressure in April:
29.95"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:
30.01"Hg - Average pressure in November:
30.1"Hg - Average pressure in December:
30.1"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed
Romeoville, IL
- Average wind speed in January:
9.7mph - Average wind speed in February:
9.6mph - Average wind speed in March:
9.3mph - Average wind speed in April:
9.5mph - Average wind speed in May:
8.1mph - Average wind speed in June:
7.1mph
The windiest month (with the highest average wind speed) is January (9.7mph).
The calmest month (with the lowest average wind speed) is August (6mph).
Average humidity
Romeoville, IL
The months with the highest relative humidity are January and February (83%).
The month with the lowest relative humidity is October (73%).
Average rainfall
Romeoville, IL
- Average rainfall in January:
1.22" - Average rainfall in February:
1.18" - Average rainfall in March:
1.3" - Average rainfall in April:
2.4" - Average rainfall in May:
2.83" - Average rainfall in June:
2.72"
- Average rainfall in July:
2.72" - Average rainfall in August:
2.48" - Average rainfall in September:
1.77" - Average rainfall in October:
2.01" - Average rainfall in November:
1.14" - Average rainfall in December:
1.06"
The wettest month (with the highest rainfall) is May (2.83").
The driest month (with the least rainfall) is December (1.06").
Average rainfall days
Romeoville, IL
- Average rainfall days in January:
5.7 days - Average rainfall days in February:
4.9 days - Average rainfall days in March:
11.8 days - Average rainfall days in April:
15 days - Average rainfall days in May:
16.4 days - Average rainfall days in June:
16.1 days
- Average rainfall days in July:
18.1 days - Average rainfall days in August:
16.3 days - Average rainfall days in September:
13.5 days - Average rainfall days in October:
11.9 days - Average rainfall days in November:
8.6 days - Average rainfall days in December:
7.1 days
The month with the highest number of rainy days is July (18.1 days).
The month with the least rainy days is February (4.9 days).
Average snowfall
Romeoville, IL
The month with the highest snowfall is January (3.11").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days
Romeoville, IL
- Average snowfall days in January:
12.1 days - Average snowfall days in February:
10.6 days - Average snowfall days in March:
6.2 days - Average snowfall days in April:
2.2 days - Average snowfall days in May:
0.1 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:
0.4 days - Average snowfall days in November:
3.1 days - Average snowfall days in December:
9.7 days
The month with the highest number of snowfall days is January (12.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
Romeoville, IL
- Average daylight in January:
9h and 4min - 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 1min - 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 6min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in January:
3h and 5min - Average sunshine in February:
3h and 5min - Average sunshine in March:
6h and 1min - Average sunshine in April:
7h and 4min - Average sunshine in May:
8h and 4min - Average sunshine in June:
9h and 4min
- Average sunshine in July:
9h and 5min - Average sunshine in August:
9h and 5min - Average sunshine in September:
8h and 4min - Average sunshine in October:
5h and 4min - Average sunshine in November:
5h and 1min - Average sunshine in December:
4h and 1min
The months with the most sunshine are July and August (Average sunshine: 9h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days
Romeoville, IL
- Average sunshine days in January:
14.8 days - Average sunshine days in February:
13.1 days - Average sunshine days in March:
14.1 days - Average sunshine days in April:
11.1 days - Average sunshine days in May:
11.7 days - Average sunshine days in June:
10.8 days
- Average sunshine days in July:
9.3 days - Average sunshine days in August:
10.8 days - Average sunshine days in September:
14.4 days - Average sunshine days in October:
16.3 days - Average sunshine days in November:
18.4 days - Average sunshine days in December:
16.2 days
The month with the most sunshine days is November (18.4 days).
The month with the least sunshine days is July (9.3 days).
Average UV index
Romeoville, IL
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover
Romeoville, IL
The month with the most cloud cover is January (Cloud cover 60).
The month with the least cloud cover is August (Cloud cover 31).
Average visibility
Romeoville, IL
The months with the highest visibility are March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January and February (5mi).
Romeoville, Illinois, USA
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