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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, is an icy winter month in Illiopolis, Illinois, with an average temperature fluctuating between 20.5°F (-6.4°C) and 32.5°F (0.3°C). January, with an average high of 32.5°F (0.3°C) and a low of 20.5°F (-6.4°C), signifies the coldest month of the year. Weather in January »
Weather in February
The last month of the winter, February, is another cold month in Illiopolis, Illinois, with temperature in the range of an average high of 37.6°F (3.1°C) and an average low of 24.6°F (-4.1°C). The transition into February is marked with an average high-temperature of a still icy 37.6°F (3.1°C), showing an insignificant shift from January's 32.5°F (0.3°C). Weather in February »
Weather in March
The first month of the spring, March, is a cool month in Illiopolis, Illinois, with an average temperature fluctuating between 50°F (10°C) and 35.2°F (1.8°C). With the arrival of March, the average high-temperature transitions from an icy 37.6°F (3.1°C) in February to a fresh 50°F (10°C). Weather in March »
Weather in April
April is an enjoyable spring month in Illiopolis, Illinois, with an average temperature varying between 62.2°F (16.8°C) and 45.9°F (7.7°C). Illiopolis in April shows a temperature shift, moving from an average high of a cool 50°F (10°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 Illiopolis, Illinois, with an average temperature ranging between max 72.9°F (22.7°C) and min 56.5°F (13.6°C). In May, the meteorological conditions change with the average high-temperature moving from a comfortable 62.2°F (16.8°C) in April to an agreeable 72.9°F (22.7°C). Weather in May »
Weather in June
The first month of the summer, June, is a warm month in Illiopolis, Illinois, with an average temperature fluctuating between 63.9°F (17.7°C) and 80.6°F (27°C). As Illiopolis enters June, the average high-temperature marginally increases from the an agreeable 72.9°F (22.7°C) of May to a warm 80.6°F (27°C). Weather in June »
Weather in July
July, the same as June, is another warm summer month in Illiopolis, Illinois, with temperature in the range of an average low of 65.7°F (18.7°C) and an average high of 82°F (27.8°C). Illiopolis witnesses the warmest weather in July, with temperatures averaging a high of 82°F (27.8°C) and a low of 65.7°F (18.7°C). The heat index value during July is calculated to be a hot 89.6°F (32°C). Weather in July »
Weather in August
The last month of the summer, August, is another warm month in Illiopolis, Illinois, with an average temperature ranging between min 63.9°F (17.7°C) and max 81.3°F (27.4°C). August's arrival brings an average high-temperature of a still moderately hot 81.3°F (27.4°C), demonstrating subtle variation from the preceding month. Weather in August »
Weather in September
September, the first month of the autumn in Illiopolis, is still a warm month, with temperature in the range of an average high of 77°F (25°C) and an average low of 58.5°F (14.7°C). Illiopolis marks the onset of September with an average high-temperature of a still moderately hot 77°F (25°C), a subtle shift from August's 81.3°F (27.4°C). Weather in September »
Weather in October
October, like September, in Illiopolis, Illinois, is another comfortable autumn month, with an average temperature fluctuating between 47.8°F (8.8°C) and 63.9°F (17.7°C). With October's onset, the weather shows a temperature decrease, transitioning from a warm 77°F (25°C) in September to an enjoyable 63.9°F (17.7°C). Weather in October »
Weather in November
November, the last month of the autumn in Illiopolis, is also a frosty month, with an average temperature varying between 49.8°F (9.9°C) and 36°F (2.2°C). The beginning of November involves a decrease in the average high-temperature, transitioning from a comfortable 63.9°F (17.7°C) in October to a frosty 49.8°F (9.9°C). Weather in November »
Weather in December
December, the first month of the winter in Illiopolis, is also a wintry month, with an average temperature fluctuating between 38.3°F (3.5°C) and 27.5°F (-2.5°C). The onset of December introduces a moderate change in Illiopolis's weather, with average high-temperatures falling from November's frosty 49.8°F (9.9°C) to a cold 38.3°F (3.5°C). Weather in December »
[Resources]Frequently asked questions
What part of the year is the coldest in Illiopolis?
In Illiopolis, the average lowest temperatures are observed in January, with a high of 32.5°F (0.3°C) and a low of 20.5°F (-6.4°C).
How much does it rain in Illiopolis?
In Illiopolis, Illinois, during the entire year, the rain falls for 141.8 days and collects up to 22.24" (565mm) of precipitation.
When does it snow in Illiopolis?
Months with snowfall are January through April, November and December.
What is the snowiest month in Illiopolis?
The month with the most snowfall in Illiopolis is January, when snow falls for 9.4 days and typically aggregates up to 2.24" (57mm) of snow.
How much does it snow in Illiopolis?
In Illiopolis, during the entire year, snow falls for 29.7 days and aggregates up to 7.13" (181mm) of snow.
What is the month with the least sunshine in Illiopolis?
January has the least sunshine of the year in Illiopolis, Illinois, with an average of 4h of sunshine.
When is the lowest UV index in Illiopolis?
The month with the lowest UV index is January, with an average maximum UV index of 1.
When is Daylight Saving Time (DST) in Illiopolis?
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 Illiopolis?
May is the month with the most rainfall. Rain falls for 17 days and accumulates 2.68" (68mm) of precipitation.
When it does not snow in Illiopolis?
May through October are months without snowfall.
When are the longest days in Illiopolis?
The month with the longest days is June, with an average of 15h and 0min of daylight.
What month has the most sunshine in Illiopolis?
June has the most sunshine of the year in Illiopolis, Illinois, with an average of 10.2h of sunshine.
When is the highest UV index in Illiopolis?
June through August, with an average maximum UV index of 6, are months with the highest UV index.
What is the hottest time of year in Illiopolis?
Illiopolis's warmest month, July, generally records average temperatures ranging from a high of 82°F (27.8°C) to a low of 65.7°F (18.7°C).
What is the most humid month in Illiopolis?
July is the most humid month in Illiopolis, Illinois, with an average relative humidity of 84%.
What is the least humid month in Illiopolis?
October is the least humid month in Illiopolis, Illinois, with an average relative humidity of 70%.
What is the driest month in Illiopolis?
December is the month with the least rainfall. Rain falls for 8.3 days and accumulates 1.1" (28mm) of precipitation.
What is the month with the shortest days in Illiopolis?
December has the shortest days of the year in Illiopolis, with an average of 9h and 24min of daylight.
Average temperature
Illiopolis, IL
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (32.5°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 (20.5°F).
Average pressure
Illiopolis, IL
- Average pressure in January:
30.15"Hg - Average pressure in February:
30.12"Hg - Average pressure in March:
30.08"Hg - Average pressure in April:
29.94"Hg - Average pressure in May:
29.95"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:
30.02"Hg - Average pressure in November:
30.12"Hg - Average pressure in December:
30.12"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed
Illiopolis, IL
- Average wind speed in January:
10.4mph - Average wind speed in February:
10.4mph - Average wind speed in March:
10.3mph - Average wind speed in April:
10.6mph - Average wind speed in May:
8.8mph - Average wind speed in June:
7.5mph
- Average wind speed in July:
6.3mph - Average wind speed in August:
6.3mph - Average wind speed in September:
7.3mph - Average wind speed in October:
9.1mph - Average wind speed in November:
9.8mph - Average wind speed in December:
9.8mph
The windiest month (with the highest average wind speed) is April (10.6mph).
The calmest months (with the lowest average wind speed) are July and August (6.3mph).
Average humidity
Illiopolis, IL
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (70%).
Average rainfall
Illiopolis, IL
- Average rainfall in January:
1.42" - Average rainfall in February:
1.18" - Average rainfall in March:
1.61" - Average rainfall in April:
2.44" - Average rainfall in May:
2.68" - Average rainfall in June:
2.48"
- Average rainfall in July:
2.05" - Average rainfall in August:
2.13" - Average rainfall in September:
1.81" - Average rainfall in October:
2.01" - Average rainfall in November:
1.34" - Average rainfall in December:
1.1"
The wettest month (with the highest rainfall) is May (2.68").
The driest month (with the least rainfall) is December (1.1").
Average rainfall days
Illiopolis, IL
- Average rainfall days in January:
6.3 days - Average rainfall days in February:
6.3 days - Average rainfall days in March:
11.7 days - Average rainfall days in April:
14.8 days - Average rainfall days in May:
17 days - Average rainfall days in June:
15.8 days
- Average rainfall days in July:
16.3 days - Average rainfall days in August:
14.3 days - Average rainfall days in September:
11.8 days - Average rainfall days in October:
10.6 days - Average rainfall days in November:
8.6 days - Average rainfall days in December:
8.3 days
The month with the highest number of rainy days is May (17 days).
The months with the least rainy days are January and February (6.3 days).
Average snowfall
Illiopolis, IL
The month with the highest snowfall is January (2.24").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days
Illiopolis, IL
- Average snowfall days in January:
9.4 days - Average snowfall days in February:
7.1 days - Average snowfall days in March:
2.9 days - Average snowfall days in April:
0.8 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:
0.1 days - Average snowfall days in October:
0.3 days - Average snowfall days in November:
2.4 days - Average snowfall days in December:
6.7 days
The month with the highest number of snowfall days is January (9.4 days).
The months with the least snowfall days are May, June, July and August (0 days).
Average daylight / Average sunshine
Illiopolis, 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 2min - Average daylight in June:
15h and 0min
- Average daylight in July:
14h and 4min - Average daylight in August:
13h and 4min - Average daylight in September:
12h and 2min - Average daylight in October:
11h and 1min - Average daylight in November:
10h and 0min - Average daylight in December:
9h and 2min
The month with the longest days is June (Average daylight: 15h and 0min).
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 2min - Average sunshine in March:
6h and 2min - Average sunshine in April:
8h and 0min - Average sunshine in May:
9h and 1min - Average sunshine in June:
10h and 1min
- Average sunshine in July:
9h and 5min - Average sunshine in August:
9h and 4min - Average sunshine in September:
9h and 0min - Average sunshine in October:
5h and 5min - Average sunshine in November:
5h and 2min - Average sunshine in December:
4h and 3min
The month with the most sunshine is June (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days
Illiopolis, IL
- Average sunshine days in January:
16.3 days - Average sunshine days in February:
14.7 days - Average sunshine days in March:
15.7 days - Average sunshine days in April:
12.8 days - Average sunshine days in May:
10.8 days - Average sunshine days in June:
11.8 days
- Average sunshine days in July:
10.9 days - Average sunshine days in August:
13.1 days - Average sunshine days in September:
15.8 days - Average sunshine days in October:
18.1 days - Average sunshine days in November:
18.9 days - Average sunshine days in December:
17.1 days
The month with the most sunshine days is November (18.9 days).
The month with the least sunshine days is May (10.8 days).
Average UV index
Illiopolis, IL
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover
Illiopolis, IL
The month with the most cloud cover is January (Cloud cover 57).
The months with the least cloud cover are June and September (Cloud cover 31).
Average visibility
Illiopolis, 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).
Illiopolis, Illinois, USA
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