Climate and monthly weather forecastCharleston, IL
Climate and monthly weather forecast
Weather in January
January, like December, in Charleston, Illinois, is another cold winter month, with an average temperature ranging between min 21.9°F (-5.6°C) and max 34°F (1.1°C). The coldest temperatures occur during January, when averages reach a peak of 34°F (1.1°C) and a low of 21.9°F (-5.6°C). Weather in January »Weather in February
February, the last month of the winter in Charleston, is also a wintry month, with an average temperature ranging between min 26.1°F (-3.3°C) and max 39°F (3.9°C). Upon the beginning of February, Charleston's high-temperatures register at a still wintry 39°F (3.9°C), closely mirroring the preceding month. Weather in February »Weather in March
The first month of the spring, March, is a cool month in Charleston, Illinois, with temperature in the range of an average high of 51.1°F (10.6°C) and an average low of 36.1°F (2.3°C). March signals a shift in the average high-temperature, moving from February's cold 39°F (3.9°C) to a cool 51.1°F (10.6°C). Weather in March »Weather in April
April in Charleston, Illinois, is an enjoyable spring month, with temperature in the range of an average high of 62.2°F (16.8°C) and an average low of 46.2°F (7.9°C). Charleston's weather shows a temperature rise with the arrival of April, moving from a fresh 51.1°F (10.6°C) in March to a comfortable 62.2°F (16.8°C). Weather in April »Weather in May
The last month of the spring, May, is an agreeable month in Charleston, Illinois, with temperature in the range of an average high of 73°F (22.8°C) and an average low of 56.7°F (13.7°C). Charleston's transition into May is marked by a temperature shift, moving from a comfortable 62.2°F (16.8°C) in April to an agreeable 73°F (22.8°C). Weather in May »Weather in June
The first month of the summer, June, is a moderately hot month in Charleston, Illinois, with an average temperature fluctuating between 81.1°F (27.3°C) and 64.2°F (17.9°C). The beginning of June marks a minor shift in the average high-temperature, moving from May's pleasant 73°F (22.8°C) to a warm 81.1°F (27.3°C). Weather in June »Weather in July
July, the same as June, is another warm summer month in Charleston, Illinois, with an average temperature varying between 65.8°F (18.8°C) and 82°F (27.8°C). The month of July sees the highest average temperatures, reaching 82°F (27.8°C) at the peak and 65.8°F (18.8°C) at the low. July's heat index is evaluated at a hot 89.6°F (32°C). Weather in July »Weather in August
August, the last month of the summer in Charleston, is another warm month, with an average temperature varying between 81.1°F (27.3°C) and 64°F (17.8°C). A minimal variation is noted in Charleston's average high-temperature at the onset of August, reaching a still warm 81.1°F (27.3°C) from July's 82°F (27.8°C). Weather in August »Weather in September
The first month of the autumn, September, is also a moderately hot month in Charleston, Illinois, with temperature in the range of an average low of 58.5°F (14.7°C) and an average high of 77.2°F (25.1°C). The onset of September brings with it an average high-temperature of a still moderately hot 77.2°F (25.1°C), showing a negligible variation from the month before. Weather in September »Weather in October
October, the same as September, is another enjoyable autumn month in Charleston, Illinois, with an average temperature ranging between max 63.9°F (17.7°C) and min 48.2°F (9°C). October brings a minor decrease, with the average high-temperature reducing from a warm 77.2°F (25.1°C) in September to a comfortable 63.9°F (17.7°C). Weather in October »Weather in November
The last month of the autumn, November, is also a frosty month in Charleston, Illinois, with an average temperature ranging between min 36.1°F (2.3°C) and max 49.8°F (9.9°C). The transition into November is accompanied by a temperature decrease, with the average high-temperature shifting from a refreshing 63.9°F (17.7°C) in October to a chilly 49.8°F (9.9°C). Weather in November »Weather in December
December, the first month of the winter in Charleston, is also an icy month, with an average temperature fluctuating between 28.8°F (-1.8°C) and 39°F (3.9°C). December involves a decrease in temperature, down from a frosty 49.8°F (9.9°C) in November to a wintry 39°F (3.9°C). Weather in December »Updated: Aug 10, 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, marked by an average high-temperature of 34°F (1.1°C) and a low-temperature of 21.9°F (-5.6°C), is the coldest month.
Throughout the year, there are 148 rainfall days, and 25.63" (651mm) of precipitation is accumulated.
January through April, October through December are months with snowfall in Charleston.
Throughout the year, there are 26.6 snowfall days, and 7.01" (178mm) of snow is accumulated.
January has the least sunshine of the year, with an average of 4h of sunshine.
The month with the least rainfall is February, when the rain falls for 7.8 days and typically collects 1.3" (33mm) of precipitation.
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.
The month with the most rainfall is April, when the rain falls for 14.9 days and typically aggregates up to 3.31" (84mm) of precipitation.
In Charleston, snow does not fall in May through September.
June has the longest days of the year, with an average of 14h and 54min of daylight.
With an average of 10.3h of sunshine, June has the most sunshine of the year.
June through August, with an average maximum UV index of 6, are months with the highest UV index in Charleston.
The month of July sees the average highest temperatures in Charleston, reaching 82°F (27.8°C) at the peak and 65.8°F (18.8°C) at the low.
The most humid month is July, with an average relative humidity of 83%.
October is the least humid month, with an average relative humidity of 70%.
December is the month with the most snowfall. Snow falls for 6 days and accumulates 2.13" (54mm) of snow.
The month with the shortest days is December, with an average of 9h and 24min of daylight.
The month with the lowest UV index is December, with an average maximum UV index of 1.
Average temperature
Charleston, IL
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (34°F).
The month with the highest average low temperature is July (65.8°F).
The coldest month (with the lowest average low temperature) is January (21.9°F).
Average pressure
Charleston, IL
- Average pressure in January:
30.15"Hg - Average pressure in February:
30.11"Hg - Average pressure in March:
30.08"Hg - Average pressure in April:
29.95"Hg - Average pressure in May:
29.96"Hg - Average pressure in June:
29.93"Hg
- Average pressure in July:
29.98"Hg - Average pressure in August:
29.98"Hg - Average pressure in September:
30.03"Hg - Average pressure in October:
30.03"Hg - Average pressure in November:
30.13"Hg - Average pressure in December:
30.13"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed
Charleston, IL
- Average wind speed in January:
10.7mph - Average wind speed in February:
10.6mph - Average wind speed in March:
10.3mph - Average wind speed in April:
10.4mph - Average wind speed in May:
8.6mph - Average wind speed in June:
7.4mph
- Average wind speed in July:
6.2mph - Average wind speed in August:
6.3mph - Average wind speed in September:
7.1mph - Average wind speed in October:
9.2mph - Average wind speed in November:
9.9mph - Average wind speed in December:
9.9mph
The windiest month (with the highest average wind speed) is January (10.7mph).
The calmest month (with the lowest average wind speed) is July (6.2mph).
Average humidity
Charleston, IL
The month with the highest relative humidity is July (83%).
The month with the lowest relative humidity is October (70%).
Average rainfall
Charleston, IL
- Average rainfall in January:
1.81" - Average rainfall in February:
1.3" - Average rainfall in March:
2.09" - Average rainfall in April:
3.31" - Average rainfall in May:
2.87" - Average rainfall in June:
2.76"
- Average rainfall in July:
2.52" - Average rainfall in August:
2.28" - Average rainfall in September:
1.38" - Average rainfall in October:
2.13" - Average rainfall in November:
1.61" - Average rainfall in December:
1.57"
The wettest month (with the highest rainfall) is April (3.31").
The driest month (with the least rainfall) is February (1.3").
Average rainfall days
Charleston, IL
- Average rainfall days in January:
8.2 days - Average rainfall days in February:
7.8 days - Average rainfall days in March:
12.5 days - Average rainfall days in April:
14.9 days - Average rainfall days in May:
16.8 days - Average rainfall days in June:
15.6 days
- Average rainfall days in July:
16.6 days - Average rainfall days in August:
14.3 days - Average rainfall days in September:
12.1 days - Average rainfall days in October:
11.1 days - Average rainfall days in November:
8.7 days - Average rainfall days in December:
9.4 days
The month with the highest number of rainy days is May (16.8 days).
The month with the least rainy days is February (7.8 days).
Average snowfall
Charleston, IL
The month with the highest snowfall is December (2.13").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days
Charleston, IL
- Average snowfall days in January:
8.1 days - Average snowfall days in February:
6.8 days - Average snowfall days in March:
3.2 days - Average snowfall days in April:
0.7 days - Average snowfall days in May:
0 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:
0.1 days - Average snowfall days in November:
1.7 days - Average snowfall days in December:
6 days
The month with the highest number of snowfall days is January (8.1 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight / Average sunshine
Charleston, IL
- Average daylight in January:
9h and 48min - Average daylight in February:
10h and 42min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 18min - Average daylight in May:
14h and 24min - Average daylight in June:
14h and 54min
- Average daylight in July:
14h and 36min - Average daylight in August:
13h and 42min - Average daylight in September:
12h and 24min - Average daylight in October:
11h and 6min - Average daylight in November:
10h and 0min - Average daylight in December:
9h and 24min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in January:
4h and 0min - Average sunshine in February:
4h and 12min - Average sunshine in March:
6h and 12min - Average sunshine in April:
8h and 0min - Average sunshine in May:
8h and 48min - Average sunshine in June:
10h and 18min
- Average sunshine in July:
9h and 54min - Average sunshine in August:
9h and 48min - Average sunshine in September:
8h and 54min - Average sunshine in October:
6h and 18min - Average sunshine in November:
5h and 12min - Average sunshine in December:
4h and 24min
The month with the most sunshine is June (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days
Charleston, IL
- Average sunshine days in January:
15.9 days - Average sunshine days in February:
14 days - Average sunshine days in March:
15.2 days - Average sunshine days in April:
12.9 days - Average sunshine days in May:
11.2 days - Average sunshine days in June:
11.5 days
- Average sunshine days in July:
10.6 days - Average sunshine days in August:
12.7 days - Average sunshine days in September:
15.7 days - Average sunshine days in October:
18.3 days - Average sunshine days in November:
17.9 days - Average sunshine days in December:
16.9 days
The month with the most sunshine days is October (18.3 days).
The month with the least sunshine days is July (10.6 days).
Average UV index
Charleston, 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
Charleston, IL
The month with the most cloud cover is January (Cloud cover 56).
The month with the least cloud cover is June (Cloud cover 31).
Average visibility
Charleston, IL
The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).
