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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
Climate and monthly weather forecast
Weather in January
January, like December, in Collinsville, Illinois, is a wintry winter month, with temperature in the range of an average low of 24.3°F (-4.3°C) and an average high of 37.4°F (3°C). January, with average temperatures reaching a high of 37.4°F (3°C) and a low of 24.3°F (-4.3°C), is the coldest month. Weather in January »
Weather in February
The last month of the winter, February, is another cold month in Collinsville, Illinois, with an average temperature fluctuating between 42.1°F (5.6°C) and 27.5°F (-2.5°C). With the onset of February, the average high-temperature stands at a still cold 42.1°F (5.6°C), closely aligned with January's 37.4°F (3°C). Weather in February »
Weather in March
March, the first month of the spring in Collinsville, is a cool month, with an average temperature ranging between max 54.1°F (12.3°C) and min 37.8°F (3.2°C). The start of March signals an increase in the average high-temperature, moving from a wintry 42.1°F (5.6°C) in February to a fresh 54.1°F (12.3°C). Weather in March »
Weather in April
April is a comfortable spring month in Collinsville, Illinois, with an average temperature varying between 64.9°F (18.3°C) and 47.8°F (8.8°C). Collinsville's weather shows a temperature rise with the arrival of April, moving from a cool 54.1°F (12.3°C) in March to an enjoyable 64.9°F (18.3°C). Weather in April »
Weather in May
The last month of the spring, May, is a warm month in Collinsville, Illinois, with an average temperature ranging between max 74.5°F (23.6°C) and min 57.6°F (14.2°C). The start of May brings a rise in the average high-temperature, moving from an enjoyable 64.9°F (18.3°C) in April to a warm 74.5°F (23.6°C). Weather in May »
Weather in June
June, the first month of the summer in Collinsville, is also a moderately hot month, with an average temperature ranging between max 83.3°F (28.5°C) and min 66.6°F (19.2°C). June's arrival brings a modest temperature shift, moving from a warm 74.5°F (23.6°C) in May to a still moderately hot 83.3°F (28.5°C). Weather in June »
Weather in July
July, like June, in Collinsville, Illinois, is a moderately hot summer month, with an average temperature ranging between min 68.2°F (20.1°C) and max 85.6°F (29.8°C). July, characterized by an average high temperature of 85.6°F (29.8°C) and a low temperature of 68.2°F (20.1°C), is generally the warmest month. In July, the heat index is evaluated at a very hot 98.6°F (37°C). Weather in July »
Weather in August
August, the last month of the summer in Collinsville, is another warm month, with an average temperature fluctuating between 84°F (28.9°C) and 66°F (18.9°C). With the advent of August, Collinsville's high-temperatures adjust to a still moderately hot 84°F (28.9°C), closely aligning with the preceding month. Weather in August »
Weather in September
The first month of the autumn, September, is still a warm month in Collinsville, Illinois, with an average temperature ranging between max 79°F (26.1°C) and min 59.9°F (15.5°C). September's presence records an average high-temperature of a still warm 79°F (26.1°C), closely mirroring August's climate. Weather in September »
Weather in October
October, like September, in Collinsville, Illinois, is another enjoyable autumn month, with an average temperature fluctuating between 66°F (18.9°C) and 48.9°F (9.4°C). As October arrives, Collinsville's weather displays a decrease in high-temperatures, transitioning from September's moderately hot 79°F (26.1°C) to a comfortable 66°F (18.9°C). Weather in October »
Weather in November
November, the last month of the autumn in Collinsville, is another cool month, with an average temperature varying between 37.6°F (3.1°C) and 52.9°F (11.6°C). Welcoming November, Collinsville observes a shift in the average high-temperature, falling from October's enjoyable 66°F (18.9°C) to a fresh 52.9°F (11.6°C). Weather in November »
Weather in December
December, the first month of the winter in Collinsville, is also a wintry month, with an average temperature varying between 30°F (-1.1°C) and 41.9°F (5.5°C). Collinsville's transition into December involves a shift in temperature, receding from a cool 52.9°F (11.6°C) in November to a wintry 41.9°F (5.5°C). Weather in December »
Updated: Jun 16, 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
What part of the year is the coldest?
In Collinsville, January is known for its average lowest temperatures, reaching a high of 37.4°F (3°C) and a low of 24.3°F (-4.3°C).
How much does it rain?
Throughout the year, there are 149.9 rainfall days, and 33.94" (862mm) of precipitation is accumulated.
When does it snow?
January through March, September, November and December are months with snowfall in Collinsville.
When does it snow the most?
The month with the most snowfall is January, when snow falls for 7 days and typically aggregates up to 2.13" (54mm) of snow.
How much does it snow?
In Collinsville, during the entire year, snow falls for 20.7 days and aggregates up to 7.13" (181mm) of snow.
What is the month with the least sunshine?
The month with the least sunshine is January, with an average of 4.5h of sunshine.
What are the months with the lowest UV index?
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index.
What is the driest month in Collinsville?
February is the month with the least rainfall. Rain falls for 8.3 days and accumulates 1.77" (45mm) of precipitation.
When is Daylight Saving Time (DST)?
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.
When it does not snow?
In Collinsville, snow does not fall in April through August and October.
What is the most humid month?
The months with the highest humidity are May, July and August, with an average relative humidity of 79%.
What is the rainiest month?
May is the month with the most rainfall. Rain falls for 17.1 days and accumulates 4.17" (106mm) of precipitation.
When is the highest UV index?
May through August, with an average maximum UV index of 6, are months with the highest UV index.
When are the longest days?
June has the longest days of the year, with an average of 14h and 48min of daylight.
What month has the most sunshine?
June has the most sunshine of the year, with an average of 10.5h of sunshine.
What month is the hottest?
The highest temperatures are recorded in July, with averages reaching a high of 85.6°F (29.8°C) and a low of 68.2°F (20.1°C).
What is the least humid month in Collinsville?
With an average relative humidity of 71%, October is the least humid month.
What is the month with the shortest days?
The month with the shortest days is December, with an average of 9h and 30min of daylight.
Average temperature
Collinsville, 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
Collinsville, 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
Collinsville, 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
Collinsville, 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
Collinsville, 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
Collinsville, 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
Collinsville, 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
Collinsville, 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
Collinsville, IL
- Average daylight in January:
9h and 5min - Average daylight in February:
10h and 5min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 1min - Average daylight in May:
14h and 2min - Average daylight in June:
14h and 5min
- 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 1min - Average daylight in December:
9h and 3min
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 3min - Average sunshine in February:
4h and 4min - Average sunshine in March:
6h and 3min - Average sunshine in April:
8h and 3min - Average sunshine in May:
9h and 2min - Average sunshine in June:
10h and 3min
- Average sunshine in July:
10h and 2min - Average sunshine in August:
10h and 1min - Average sunshine in September:
9h and 2min - Average sunshine in October:
6h and 1min - Average sunshine in November:
5h and 4min - Average sunshine in December:
4h and 5min
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
Collinsville, 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
Collinsville, 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
Collinsville, 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
Collinsville, 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).