Climate and monthly weather forecastCaseyville, IL
Climate and monthly weather forecast
Weather in January
January, the same as December, is a wintry winter month in Caseyville, Illinois, with an average temperature ranging between max 37.4°F (3°C) and min 24.3°F (-4.3°C). With average temperatures fluctuating between a high of 37.4°F (3°C) and a low of 24.3°F (-4.3°C), January stands out as the coldest month. Weather in January »Weather in February
The last month of the winter, February, is also an icy month in Caseyville, Illinois, with temperature in the range of an average low of 27.5°F (-2.5°C) and an average high of 42.1°F (5.6°C). February's beginning signals an average high-temperature of a still icy 42.1°F (5.6°C), barely different from January's 37.4°F (3°C). Weather in February »Weather in March
The first month of the spring, March, is a fresh month in Caseyville, Illinois, with an average temperature fluctuating between 54.1°F (12.3°C) and 37.8°F (3.2°C). The start of March signals an increase in the average high-temperature, moving from an icy 42.1°F (5.6°C) in February to a fresh 54.1°F (12.3°C). Weather in March »Weather in April
April in Caseyville, Illinois, is an enjoyable spring month, with an average temperature varying between 64.9°F (18.3°C) and 47.8°F (8.8°C). Caseyville's transition into April is marked by a rise in the average high-temperature, advancing from a fresh 54.1°F (12.3°C) in March to a refreshing 64.9°F (18.3°C). Weather in April »Weather in May
The last month of the spring, May, is a warm month in Caseyville, Illinois, with temperature in the range of an average low of 57.6°F (14.2°C) and an average high of 74.5°F (23.6°C). An escalation in the average high-temperature is seen with the onset of May, moving from a refreshing 64.9°F (18.3°C) in April to a warm 74.5°F (23.6°C). Weather in May »Weather in June
The first month of the summer, June, is also a moderately hot month in Caseyville, Illinois, with an average temperature varying between 83.3°F (28.5°C) and 66.6°F (19.2°C). A soft shift in the average high-temperature is noticeable in June, transitioning from a moderately hot 74.5°F (23.6°C) in May to a still warm 83.3°F (28.5°C). Weather in June »Weather in July
July, like June, in Caseyville, Illinois, is a moderately hot summer month, with an average temperature ranging between max 85.6°F (29.8°C) and min 68.2°F (20.1°C). July is Caseyville's warmest month, registering average high temperatures of 85.6°F (29.8°C) and lows of 68.2°F (20.1°C). The heat index value during July is estimated at a very hot 98.6°F (37°C). Weather in July »Weather in August
The last month of the summer, August, is also a moderately hot month in Caseyville, Illinois, with an average temperature varying between 66°F (18.9°C) and 84°F (28.9°C). The onset of August marks an average high-temperature of a still moderately hot 84°F (28.9°C), hardly differing from July's 85.6°F (29.8°C). Weather in August »Weather in September
September, the first month of the autumn in Caseyville, is also a moderately hot month, with temperature in the range of an average low of 59.9°F (15.5°C) and an average high of 79°F (26.1°C). The weather during September records an average high-temperature of a still warm 79°F (26.1°C), closely mirroring the preceding month. Weather in September »Weather in October
October, like September, in Caseyville, Illinois, is another enjoyable autumn month, with an average temperature fluctuating between 48.9°F (9.4°C) and 66°F (18.9°C). A moderate decline in the average high-temperature is seen during October, decreasing from a warm 79°F (26.1°C) in September to a comfortable 66°F (18.9°C). Weather in October »Weather in November
November, the last month of the autumn in Caseyville, is also a fresh month, with temperature in the range of an average low of 37.6°F (3.1°C) and an average high of 52.9°F (11.6°C). The shift from October to November corresponds with a decrease in the average high-temperature, down to a cool 52.9°F (11.6°C) from an enjoyable 66°F (18.9°C). Weather in November »Weather in December
The first month of the winter, December, is still a cold month in Caseyville, Illinois, with temperature in the range of an average low of 30°F (-1.1°C) and an average high of 41.9°F (5.5°C). Caseyville's weather in December involves a decrease in the average high-temperature, moving down from November's cool 52.9°F (11.6°C) to a wintry 41.9°F (5.5°C). Weather in December »Updated: Jul 27, 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
With its average high temperature of 37.4°F (3°C) and a low of 24.3°F (-4.3°C), January is regarded as the coldest month.
Throughout the year, there are 149.9 rainfall days, and 33.94" (862mm) of precipitation is accumulated.
Months with snowfall in Caseyville are January through March, September, November and December.
January is the month with the most snowfall. Snow falls for 7 days and accumulates 2.13" (54mm) of snow.
Throughout the year, there are 20.7 snowfall days, and 7.13" (181mm) of snow is accumulated.
With an average of 4.5h of sunshine, January has the least sunshine of the year.
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 2.
The month with the least rainfall is February, when the rain falls for 8.3 days and typically collects 1.77" (45mm) 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.
In Caseyville, snow does not fall in April through August and October.
May, July and August, with an average relative humidity of 79%, are most humid months.
The month with the most rainfall in Caseyville is May, when the rain falls for 17.1 days and typically aggregates up to 4.17" (106mm) of precipitation.
May through August, with an average maximum UV index of 6, are months with the highest UV index.
The month with the longest days is June, with an average of 14h and 48min of daylight.
June has the most sunshine of the year, with an average of 10.5h of sunshine.
July, recording an average high temperature of 85.6°F (29.8°C) and a low temperature of 68.2°F (20.1°C), is Caseyville's warmest month.
October is the least humid month, with an average relative humidity of 71%.
The month with the shortest days is December, with an average of 9h and 30min of daylight.
Average temperature
Caseyville, IL
The warmest month (with the highest average high temperature) is July (85.6°F).
The month with the lowest average high temperature is January (37.4°F).
The month with the highest average low temperature is July (68.2°F).
The coldest month (with the lowest average low temperature) is January (24.3°F).
Average pressure
Caseyville, IL
- Average pressure in January:
30.16"Hg - Average pressure in February:
30.12"Hg - Average pressure in March:
30.07"Hg - Average pressure in April:
29.94"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:
30.02"Hg - Average pressure in October:
30.03"Hg - Average pressure in November:
30.12"Hg - Average pressure in December:
30.13"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed
Caseyville, IL
- Average wind speed in January:
9.5mph - Average wind speed in February:
9.4mph - Average wind speed in March:
9.3mph - Average wind speed in April:
9.1mph - Average wind speed in May:
7.5mph - Average wind speed in June:
6.6mph
- Average wind speed in July:
5.6mph - Average wind speed in August:
5.7mph - Average wind speed in September:
6.2mph - Average wind speed in October:
8mph - Average wind speed in November:
8.7mph - Average wind speed in December:
8.8mph
The windiest month (with the highest average wind speed) is January (9.5mph).
The calmest month (with the lowest average wind speed) is July (5.6mph).
Average humidity
Caseyville, IL
The months with the highest relative humidity are May, July and August (79%).
The month with the lowest relative humidity is October (71%).
Average rainfall
Caseyville, IL
- Average rainfall in January:
2.2" - Average rainfall in February:
1.77" - Average rainfall in March:
2.6" - Average rainfall in April:
3.5" - Average rainfall in May:
4.17" - Average rainfall in June:
3.9"
- Average rainfall in July:
3.31" - Average rainfall in August:
3.35" - Average rainfall in September:
2.13" - Average rainfall in October:
2.76" - Average rainfall in November:
2.05" - Average rainfall in December:
2.2"
The wettest month (with the highest rainfall) is May (4.17").
The driest month (with the least rainfall) is February (1.77").
Average rainfall days
Caseyville, IL
- Average rainfall days in January:
7.8 days - Average rainfall days in February:
8.3 days - Average rainfall days in March:
13.9 days - Average rainfall days in April:
15.4 days - Average rainfall days in May:
17.1 days - Average rainfall days in June:
15.5 days
- Average rainfall days in July:
16.4 days - Average rainfall days in August:
13.1 days - Average rainfall days in September:
12.3 days - Average rainfall days in October:
11.1 days - Average rainfall days in November:
10.6 days - Average rainfall days in December:
8.4 days
The month with the highest number of rainy days is May (17.1 days).
The month with the least rainy days is January (7.8 days).
Average snowfall
Caseyville, IL
The month with the highest snowfall is January (2.13").
The months with the least snowfall are April, May, June, July, August and October (0").
Average snowfall days
Caseyville, IL
- Average snowfall days in January:
7 days - Average snowfall days in February:
6 days - Average snowfall days in March:
2.2 days - Average snowfall days in April:
0.3 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:
0.1 days - Average snowfall days in November:
1.2 days - Average snowfall days in December:
3.8 days
The month with the highest number of snowfall days is January (7 days).
The months with the least snowfall days are May, June, July and August (0 days).
Average daylight / Average sunshine
Caseyville, IL
- Average daylight in January:
9h and 48min - Average daylight in February:
10h and 48min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 12min - Average daylight in May:
14h and 18min - Average daylight in June:
14h and 48min
- Average daylight in July:
14h and 36min - Average daylight in August:
13h and 36min - Average daylight in September:
12h and 24min - Average daylight in October:
11h and 12min - Average daylight in November:
10h and 6min - Average daylight in December:
9h and 30min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in January:
4h and 30min - Average sunshine in February:
4h and 36min - Average sunshine in March:
6h and 30min - Average sunshine in April:
8h and 30min - Average sunshine in May:
9h and 24min - Average sunshine in June:
10h and 30min
- Average sunshine in July:
10h and 18min - Average sunshine in August:
10h and 6min - Average sunshine in September:
9h and 18min - Average sunshine in October:
6h and 12min - Average sunshine in November:
5h and 36min - Average sunshine in December:
4h and 48min
The month with the most sunshine is June (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 4h and 30min).
Average sunshine days
Caseyville, IL
- Average sunshine days in January:
17 days - Average sunshine days in February:
14.5 days - Average sunshine days in March:
14.3 days - Average sunshine days in April:
13.1 days - Average sunshine days in May:
11.6 days - Average sunshine days in June:
11.8 days
- Average sunshine days in July:
12.7 days - Average sunshine days in August:
15.3 days - Average sunshine days in September:
15.1 days - Average sunshine days in October:
18.2 days - Average sunshine days in November:
17.9 days - Average sunshine days in December:
18.6 days
The month with the most sunshine days is December (18.6 days).
The month with the least sunshine days is May (11.6 days).
Average UV index
Caseyville, IL
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover
Caseyville, IL
The month with the most cloud cover is January (Cloud cover 51).
The months with the least cloud cover are June and August (Cloud cover 28).
Average visibility
Caseyville, IL
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
