Climate and monthly weather forecastMattoon, IL
Climate and monthly weather forecast
Weather in January
January, like December, in Mattoon, Illinois, is another cold winter month, with an average temperature fluctuating between 21.9°F (-5.6°C) and 34°F (1.1°C). Temperature records mark January as the coldest month, with highs averaging 34°F (1.1°C) and lows at 21.9°F (-5.6°C). Weather in January »Weather in February
February, the last month of the winter in Mattoon, is another cold month, with an average temperature varying between 39°F (3.9°C) and 26.1°F (-3.3°C). February ushers in an average high-temperature of a still icy 39°F (3.9°C), aligning closely with the preceding month. Weather in February »Weather in March
March, the first month of the spring in Mattoon, is a cool month, with an average temperature fluctuating between 51.1°F (10.6°C) and 36.1°F (2.3°C). The rise of average high-temperatures is seen in March, with an increase from an icy 39°F (3.9°C) in February to a cool 51.1°F (10.6°C). Weather in March »Weather in April
April is a refreshing spring month in Mattoon, Illinois, with an average temperature fluctuating between 62.2°F (16.8°C) and 46.2°F (7.9°C). With the beginning of April, Mattoon's average high-temperature sees an increase, transitioning from a cool 51.1°F (10.6°C) in March to a comfortable 62.2°F (16.8°C). Weather in April »Weather in May
May, the last month of the spring in Mattoon, is a pleasant month, with an average temperature fluctuating between 73°F (22.8°C) and 56.7°F (13.7°C). May's arrival is marked by an increase in the average high-temperature, moving from a refreshing 62.2°F (16.8°C) in April to an agreeable 73°F (22.8°C). Weather in May »Weather in June
June, the first month of the summer in Mattoon, is a moderately hot month, with an average temperature fluctuating between 64.2°F (17.9°C) and 81.1°F (27.3°C). June's arrival coincides with a subtle temperature rise, moving from May's pleasant 73°F (22.8°C) to a moderately hot 81.1°F (27.3°C). Weather in June »Weather in July
July, like June, in Mattoon, Illinois, is a moderately hot summer month, with an average temperature ranging between min 65.8°F (18.8°C) and max 82°F (27.8°C). July stands out as Mattoon's warmest month, with temperatures ranging between an average high of 82°F (27.8°C) and a low of 65.8°F (18.8°C). July's average heat index is calculated to be a tropical 89.6°F (32°C). Weather in July »Weather in August
August, the last month of the summer in Mattoon, is also a moderately hot month, with an average temperature ranging between max 81.1°F (27.3°C) and min 64°F (17.8°C). The advent of August signifies a minor shift to an average high-temperature of a still warm 81.1°F (27.3°C), aligning closely with July. Weather in August »Weather in September
September, the first month of the autumn in Mattoon, is also a moderately hot month, with an average temperature fluctuating between 58.5°F (14.7°C) and 77.2°F (25.1°C). September brings a marginal elevation to a still moderately hot 77.2°F (25.1°C) from August's 81.1°F (27.3°C) in Mattoon's average high-temperatures. Weather in September »Weather in October
October, like September, in Mattoon, Illinois, is another comfortable autumn month, with an average temperature varying between 48.2°F (9°C) and 63.9°F (17.7°C). With the onset of October, Mattoon's average high-temperature adjusts, receding from September's warm 77.2°F (25.1°C) to an enjoyable 63.9°F (17.7°C). Weather in October »Weather in November
The last month of the autumn, November, is another chilly month in Mattoon, Illinois, with an average temperature varying between 36.1°F (2.3°C) and 49.8°F (9.9°C). The arrival of November signals a shift in temperature, down 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
The first month of the winter, December, is still a cold month in Mattoon, Illinois, with an average temperature varying between 28.8°F (-1.8°C) and 39°F (3.9°C). With the onset of December, Mattoon experiences a modest temperature adjustment, with the average high-temperature receding from a frosty 49.8°F (9.9°C) in November to a wintry 39°F (3.9°C). Weather in December »Updated: Jul 5, 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
In Mattoon, January is the coldest month, with temperatures averaging a high of 34°F (1.1°C) and a low of 21.9°F (-5.6°C).
Throughout the year, there are 148 rainfall days, and 25.63" (651mm) of precipitation is accumulated.
Months with snowfall are January through April, October through December.
In Mattoon, during the entire year, snow falls for 26.6 days and aggregates up to 7.01" (178mm) of snow.
With an average of 4h of sunshine, January has the least sunshine of the year.
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.
May through September are months without snowfall.
June has the longest days of the year, with an average of 14h and 54min of daylight.
June has the most sunshine of the year in Mattoon, with an average of 10.3h of sunshine.
The months with the highest UV index are June through August, with an average maximum UV index of 6.
July, known for its average high temperature of 82°F (27.8°C) and an average low temperature of 65.8°F (18.8°C), is the warmest month.
The most humid month is July, with an average relative humidity of 83%.
With an average relative humidity of 70%, October is the least humid month.
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
Mattoon, 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
Mattoon, 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
Mattoon, 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
Mattoon, IL
The month with the highest relative humidity is July (83%).
The month with the lowest relative humidity is October (70%).
Average rainfall
Mattoon, 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
Mattoon, 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
Mattoon, 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
Mattoon, 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
Mattoon, 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
Mattoon, 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
Mattoon, 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
Mattoon, 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
Mattoon, 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).
