Climate and monthly weather forecastLemont, IL
Climate and monthly weather forecast
Weather in January
January, the same as December, in Lemont, Illinois, is a freezing cold winter month, with an average temperature varying between 17.1°F (-8.3°C) and 28.8°F (-1.8°C). January, with its high-temperature average of 28.8°F (-1.8°C) and a low-temperature average of 17.1°F (-8.3°C), is the coldest month. Weather in January »Weather in February
The last month of the winter, February, is an icy month in Lemont, Illinois, with an average temperature varying between 32.5°F (0.3°C) and 19.9°F (-6.7°C). Lemont's February showcases an average high-temperature of an icy 32.5°F (0.3°C), hardly distinct from January's 28.8°F (-1.8°C). Weather in February »Weather in March
March, the first month of the spring in Lemont, is a chilly month, with an average temperature ranging between max 45.7°F (7.6°C) and min 32°F (0°C). Lemont's March weather shows an increase in high-temperatures, moving from February's icy 32.5°F (0.3°C) to a frosty 45.7°F (7.6°C). Weather in March »Weather in April
April is a refreshing spring month in Lemont, Illinois, with an average temperature varying between 57°F (13.9°C) and 41°F (5°C). The arrival of April brings an increase in high-temperatures, moving from a frosty 45.7°F (7.6°C) in March to a moderate 57°F (13.9°C). Weather in April »Weather in May
May, the last month of the spring in Lemont, is an agreeable month, with an average temperature varying between 69.4°F (20.8°C) and 52.3°F (11.3°C). May sees a rise in the average high-temperature, climbing 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
June, the first month of the summer in Lemont, is a warm month, with an average temperature ranging between max 78.6°F (25.9°C) and min 61.3°F (16.3°C). With the onset of June, Lemont experiences a temperature shift, with the average high-temperature moving from an agreeable 69.4°F (20.8°C) in May to a moderately hot 78.6°F (25.9°C). Weather in June »Weather in July
July, like June, in Lemont, Illinois, is another warm summer month, with an average temperature fluctuating between 65.7°F (18.7°C) and 81.9°F (27.7°C). July is the warmest month of the year, registering average temperatures as high as 81.9°F (27.7°C) and as low as 65.7°F (18.7°C). The heat index in July is appraised at a tropical 87.8°F (31°C). Weather in July »Weather in August
The last month of the summer, August, is also a moderately hot month in Lemont, Illinois, with temperature in the range of an average high of 80.2°F (26.8°C) and an average low of 63.9°F (17.7°C). Lemont experiences a transition to a still moderately hot 80.2°F (26.8°C) in average high-temperatures with the arrival of August, not greatly differing from July's 81.9°F (27.7°C). Weather in August »Weather in September
September, the first month of the autumn in Lemont, is still a warm month, with an average temperature fluctuating between 57.4°F (14.1°C) and 74.3°F (23.5°C). As September commences, the average high-temperature subtly reduces, transitioning from 80.2°F (26.8°C) in August 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 Lemont, Illinois, with an average temperature fluctuating between 45.5°F (7.5°C) and 60.6°F (15.9°C). Transition from September to October is accompanied by a temperature drop, with average high-temperatures decreasing from a warm 74.3°F (23.5°C) to a mild 60.6°F (15.9°C). Weather in October »Weather in November
November, the last month of the autumn in Lemont, is also a frosty month, with an average temperature fluctuating between 33.4°F (0.8°C) and 46.6°F (8.1°C). Onset of November comes with a temperature decline, the average high falling from a mild 60.6°F (15.9°C) in October to a chilly 46.6°F (8.1°C). Weather in November »Weather in December
The first month of the winter, December, is also a wintry month in Lemont, Illinois, with an average temperature fluctuating between 24.6°F (-4.1°C) and 34.7°F (1.5°C). A moderate decline in the average high-temperature is seen during December, decreasing from a chilly 46.6°F (8.1°C) in November to an icy 34.7°F (1.5°C). Weather in December »Updated: Jul 7, 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
January, with its high-temperature average of 28.8°F (-1.8°C) and a low-temperature average of 17.1°F (-8.3°C), is the coldest month.
The months with the highest humidity are January and February, with an average relative humidity of 83%.
Throughout the year, there are 145.4 rainfall days, and 22.83" (580mm) of precipitation is accumulated.
January through May, October through December are months with snowfall.
January is the month with the most snowfall. Snow falls for 12.1 days and accumulates 3.11" (79mm) of snow.
Throughout the year, there are 44.4 snowfall days, and 11.93" (303mm) of snow is accumulated.
With an average of 3.8h of sunshine, January has the least sunshine of the year.
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts in Lemont, 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.
The month with the most rainfall is May, when the rain falls for 16.4 days and typically aggregates up to 2.83" (72mm) of precipitation.
In Lemont, snow does not fall in June through September.
The month with the longest days is June, with an average of 15h and 12min of daylight.
June through August, with an average maximum UV index of 6, are months with the highest UV index.
The warmest period tends to be July, when average temperatures fluctuate between a high of 81.9°F (27.7°C) and a low of 65.7°F (18.7°C).
The months with the most sunshine are July and August, with an average of 9.9h of sunshine.
The least humid month is October, with an average relative humidity of 73%.
December is the month with the least rainfall. Rain falls for 7.1 days and accumulates 1.06" (27mm) of precipitation.
December has the shortest days of the year, with an average of 9h and 12min of daylight.
December is the month with the lowest UV index, with an average maximum UV index of 1.
Average temperature
Lemont, 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
Lemont, 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
Lemont, 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
Lemont, 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
Lemont, 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
Lemont, 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
Lemont, 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
Lemont, 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
Lemont, IL
- Average daylight in January:
9h and 36min - Average daylight in February:
10h and 36min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 24min - Average daylight in May:
14h and 36min - Average daylight in June:
15h and 12min
- Average daylight in July:
14h and 48min - Average daylight in August:
13h and 48min - Average daylight in September:
12h and 30min - Average daylight in October:
11h and 6min - Average daylight in November:
9h and 48min - Average daylight in December:
9h and 12min
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 12min).
- Average sunshine in January:
3h and 48min - Average sunshine in February:
3h and 54min - Average sunshine in March:
6h and 6min - Average sunshine in April:
7h and 36min - Average sunshine in May:
8h and 42min - Average sunshine in June:
9h and 42min
- Average sunshine in July:
9h and 54min - Average sunshine in August:
9h and 54min - Average sunshine in September:
8h and 42min - Average sunshine in October:
5h and 42min - Average sunshine in November:
5h and 6min - Average sunshine in December:
4h and 6min
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
Lemont, 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
Lemont, 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
Lemont, 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
Lemont, 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).
