Expand
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, like December, in Clayton, Illinois, is a wintry winter month, with an average temperature ranging between min 20.3°F (-6.5°C) and max 32.7°F (0.4°C). Clayton's temperature records reveal January as the coldest month, marked by average highs of 32.7°F (0.4°C) and lows of 20.3°F (-6.5°C). Weather in January »
Weather in February
February, the last month of the winter in Clayton, is also an icy month, with an average temperature ranging between max 37.9°F (3.3°C) and min 24.3°F (-4.3°C). In Clayton, February's average high-temperature stands at a still cold 37.9°F (3.3°C), closely related to the preceding month. Weather in February »
Weather in March
March, the first month of the spring in Clayton, is a fresh month, with an average temperature ranging between min 35.2°F (1.8°C) and max 50.9°F (10.5°C). As February gives way to March, the average high-temperature displays an increase, moving from an icy 37.9°F (3.3°C) to a cool 50.9°F (10.5°C). Weather in March »
Weather in April
April in Clayton, Illinois, is an enjoyable spring month, with an average temperature varying between 62.6°F (17°C) and 45.3°F (7.4°C). With the arrival of April, the average high-temperature transitions from a cool 50.9°F (10.5°C) in March to an enjoyable 62.6°F (17°C). Weather in April »
Weather in May
May, the last month of the spring in Clayton, is a pleasant month, with an average temperature varying between 55.6°F (13.1°C) and 72°F (22.2°C). In Clayton, the average high-temperature in May increases from a comfortable 62.6°F (17°C) in April to a pleasant 72°F (22.2°C). Weather in May »
Weather in June
The first month of the summer, June, is a warm month in Clayton, Illinois, with an average temperature varying between 81°F (27.2°C) and 64°F (17.8°C). June marks a rise in the average high-temperature, moving from May's agreeable 72°F (22.2°C) to a warm 81°F (27.2°C). Weather in June »
Weather in July
July, like June, in Clayton, Illinois, is a moderately hot summer month, with temperature in the range of an average high of 83.7°F (28.7°C) and an average low of 66.6°F (19.2°C). Clayton's warmest weather arrives in July, when temperatures average a high of 83.7°F (28.7°C) and a low of 66.6°F (19.2°C). July's average heat index is calculated to be a hot 93.2°F (34°C). Weather in July »
Weather in August
The last month of the summer, August, is another warm month in Clayton, Illinois, with an average temperature varying between 82.9°F (28.3°C) and 64.4°F (18°C). Clayton sees the arrival of August with an average high-temperature of a still warm 82.9°F (28.3°C), indicating a subtle variation from July. Weather in August »
Weather in September
September, the first month of the autumn in Clayton, is also a moderately hot month, with temperature in the range of an average low of 58.1°F (14.5°C) and an average high of 77.7°F (25.4°C). The onset of September manifests an average high-temperature of a still warm 77.7°F (25.4°C), demonstrating a minor variation from the preceding month. Weather in September »
Weather in October
October, like September, in Clayton, Illinois, is another enjoyable autumn month, with an average temperature varying between 46.8°F (8.2°C) and 63.9°F (17.7°C). With October's arrival, Clayton sees a decrease in average high-temperatures, moving from a moderately hot 77.7°F (25.4°C) in September to a refreshing 63.9°F (17.7°C). Weather in October »
Weather in November
November, the last month of the autumn in Clayton, is another cool month, with an average temperature fluctuating between 35.6°F (2°C) and 50°F (10°C). The move into November indicates a reduction in the average high-temperature, down from October's refreshing 63.9°F (17.7°C) to a cool 50°F (10°C). Weather in November »
Weather in December
The first month of the winter, December, is still a cold month in Clayton, Illinois, with an average temperature ranging between max 38.5°F (3.6°C) and min 26.8°F (-2.9°C). The start of December signals a decrease in the average high-temperature, transitioning from a cool 50°F (10°C) in November to a cold 38.5°F (3.6°C). Weather in December »
Updated: Jul 23, 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 is the coldest time of year?
The coldest temperatures occur during January, when averages reach a peak of 32.7°F (0.4°C) and a low of 20.3°F (-6.5°C).
What is the driest month?
The month with the least rainfall in Clayton is January, when the rain falls for 5.3 days and typically collects 0.98" (25mm) of precipitation.
How much does it rain?
Throughout the year, there are 132 rainfall days, and 22.17" (563mm) of precipitation is accumulated.
When does it snow?
January through April, November and December are months with snowfall.
When does it snow the most?
January is the month with the most snowfall. Snow falls for 7.8 days and accumulates 3.19" (81mm) of snow.
How much does it snow?
Throughout the year, there are 23.8 snowfall days, and 8.5" (216mm) of snow is accumulated.
What is the month with the least sunshine?
January has the least sunshine of the year, with an average of 4.3h of sunshine.
When is the lowest UV index?
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 2.
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.
What is the rainiest month?
May is the month with the most rainfall. Rain falls for 16.9 days and accumulates 3.23" (82mm) of precipitation.
When it does not snow in Clayton?
May through October are months without snowfall.
When are the longest days in Clayton?
The month with the longest days is June, with an average of 15h and 0min of daylight.
What are the months with the most sunshine?
The months with the most sunshine are June and July, with an average of 10.2h of sunshine.
What is the month with the highest UV index?
June through August, with an average maximum UV index of 6, are months with the highest UV index.
What month is the hottest?
The warmest temperatures occur during July, when averages reach a peak of 83.7°F (28.7°C) and a low of 66.6°F (19.2°C).
What is the most humid month?
With an average relative humidity of 82%, July is the most humid month.
What is the least humid month?
The least humid month is October, with an average relative humidity of 71%.
What is the month with the shortest days in Clayton?
The month with the shortest days is December, with an average of 9h and 24min of daylight.
Average temperature
Clayton, IL
The warmest month (with the highest average high temperature) is July (83.7°F).
The month with the lowest average high temperature is January (32.7°F).
The month with the highest average low temperature is July (66.6°F).
The coldest month (with the lowest average low temperature) is January (20.3°F).
Average pressure
Clayton, IL
- Average pressure in January:
30.15"Hg - Average pressure in February:
30.12"Hg - Average pressure in March:
30.07"Hg - Average pressure in April:
29.93"Hg - Average pressure in May:
29.94"Hg - Average pressure in June:
29.91"Hg
- Average pressure in July:
29.96"Hg - Average pressure in August:
29.97"Hg - Average pressure in September:
30.02"Hg - Average pressure in October:
30.02"Hg - Average pressure in November:
30.11"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 (29.91"Hg).
Average wind speed
Clayton, IL
- Average wind speed in January:
10.2mph - Average wind speed in February:
10.1mph - Average wind speed in March:
10mph - Average wind speed in April:
10.1mph - Average wind speed in May:
8.3mph - Average wind speed in June:
7.4mph
- Average wind speed in July:
6.3mph - Average wind speed in August:
6.4mph - Average wind speed in September:
7.1mph - Average wind speed in October:
8.9mph - Average wind speed in November:
9.8mph - Average wind speed in December:
9.7mph
The windiest month (with the highest average wind speed) is January (10.2mph).
The calmest month (with the lowest average wind speed) is July (6.3mph).
Average humidity
Clayton, IL
The month with the highest relative humidity is July (82%).
The month with the lowest relative humidity is October (71%).
Average rainfall
Clayton, IL
- Average rainfall in January:
0.98" - Average rainfall in February:
1.06" - Average rainfall in March:
1.85" - Average rainfall in April:
2.44" - Average rainfall in May:
3.23" - Average rainfall in June:
2.48"
- Average rainfall in July:
1.81" - Average rainfall in August:
1.89" - Average rainfall in September:
2.2" - Average rainfall in October:
1.69" - Average rainfall in November:
1.46" - Average rainfall in December:
1.06"
The wettest month (with the highest rainfall) is May (3.23").
The driest month (with the least rainfall) is January (0.98").
Average rainfall days
Clayton, IL
- Average rainfall days in January:
5.3 days - Average rainfall days in February:
5.3 days - Average rainfall days in March:
12.8 days - Average rainfall days in April:
14.8 days - Average rainfall days in May:
16.9 days - Average rainfall days in June:
15 days
- Average rainfall days in July:
14.3 days - Average rainfall days in August:
12.2 days - Average rainfall days in September:
10.2 days - Average rainfall days in October:
10.4 days - Average rainfall days in November:
8.4 days - Average rainfall days in December:
6.4 days
The month with the highest number of rainy days is May (16.9 days).
The months with the least rainy days are January and February (5.3 days).
Average snowfall
Clayton, IL
The month with the highest snowfall is January (3.19").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days
Clayton, IL
- Average snowfall days in January:
7.8 days - Average snowfall days in February:
5.7 days - Average snowfall days in March:
3.3 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 days - Average snowfall days in October:
0.1 days - Average snowfall days in November:
1.4 days - Average snowfall days in December:
4.7 days
The month with the highest number of snowfall days is January (7.8 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight / Average sunshine
Clayton, 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 2min - Average sunshine in February:
4h and 3min - Average sunshine in March:
6h and 2min - Average sunshine in April:
8h and 1min - Average sunshine in May:
8h and 5min - Average sunshine in June:
10h and 1min
- Average sunshine in July:
10h and 1min - Average sunshine in August:
9h and 5min - Average sunshine in September:
9h and 2min - Average sunshine in October:
5h and 4min - Average sunshine in November:
5h and 2min - Average sunshine in December:
4h and 4min
The months with the most sunshine are June and July (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 4h and 18min).
Average sunshine days
Clayton, IL
- Average sunshine days in January:
20 days - Average sunshine days in February:
17.2 days - Average sunshine days in March:
14.9 days - Average sunshine days in April:
13.8 days - Average sunshine days in May:
11.4 days - Average sunshine days in June:
12.2 days
- Average sunshine days in July:
14.3 days - Average sunshine days in August:
16.3 days - Average sunshine days in September:
18.2 days - Average sunshine days in October:
19.1 days - Average sunshine days in November:
19.5 days - Average sunshine days in December:
19.4 days
The month with the most sunshine days is January (20 days).
The month with the least sunshine days is May (11.4 days).
Average UV index
Clayton, IL
The months with the highest UV index are 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
Clayton, IL
The month with the most cloud cover is January (Cloud cover 54).
The months with the least cloud cover are July, August and September (Cloud cover 30).
Average visibility
Clayton, 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).
Clayton, Illinois, USA
Weather forecast for your location
1. Click Locate me button
2. Allow the app to use your location
2. Allow the app to use your location