Climate and monthly weather forecastWilmington, IL
Climate and monthly weather forecast
Weather in January
January, like December, is a freezing cold winter month in Wilmington, Illinois, with an average temperature varying between 17.8°F (-7.9°C) and 29.7°F (-1.3°C). Wilmington's coldest temperatures are experienced in January, with average high temperatures of 29.7°F (-1.3°C) and lows of 17.8°F (-7.9°C). Weather in January »Weather in February
February, the last month of the winter in Wilmington, is a wintry month, with an average temperature ranging between min 20.8°F (-6.2°C) and max 33.6°F (0.9°C). Wilmington's shift into February is marked by a subtle change to a wintry 33.6°F (0.9°C) from January's 29.7°F (-1.3°C) in temperature. Weather in February »Weather in March
The first month of the spring, March, is a frosty month in Wilmington, Illinois, with temperature in the range of an average low of 32.5°F (0.3°C) and an average high of 47.1°F (8.4°C). The commencement of March sees a shift in the average high-temperature, moving from an icy 33.6°F (0.9°C) in February to a chilly 47.1°F (8.4°C). Weather in March »Weather in April
April in Wilmington, Illinois, is a mild spring month, with an average temperature fluctuating between 42.4°F (5.8°C) and 58.8°F (14.9°C). Wilmington's April weather shows an increase in high-temperatures, moving from March's frosty 47.1°F (8.4°C) to a moderate 58.8°F (14.9°C). Weather in April »Weather in May
May, the last month of the spring in Wilmington, is a pleasant month, with an average temperature fluctuating between 54°F (12.2°C) and 70.7°F (21.5°C). With the beginning of May, Wilmington's average high-temperature sees an increase, transitioning from a refreshing 58.8°F (14.9°C) in April to an agreeable 70.7°F (21.5°C). Weather in May »Weather in June
June, the first month of the summer in Wilmington, is a moderately hot month, with an average temperature varying between 79.2°F (26.2°C) and 61.9°F (16.6°C). Wilmington's June weather indicates a minor increase in high-temperatures, edging from May's agreeable 70.7°F (21.5°C) to a moderately hot 79.2°F (26.2°C). Weather in June »Weather in July
July, like June, in Wilmington, Illinois, is a moderately hot summer month, with an average temperature varying between 64.6°F (18.1°C) and 81.1°F (27.3°C). Wilmington witnesses the warmest weather in July, with temperatures averaging a high of 81.1°F (27.3°C) and a low of 64.6°F (18.1°C). In July, the average heat index is appraised at a tropical 87.8°F (31°C). Weather in July »Weather in August
The last month of the summer, August, is also a moderately hot month in Wilmington, Illinois, with an average temperature ranging between min 62.6°F (17°C) and max 79.7°F (26.5°C). The transition into August shows a subtle variation to a still warm 79.7°F (26.5°C) from July's 81.1°F (27.3°C) in the average high-temperature. Weather in August »Weather in September
September, the first month of the autumn in Wilmington, is still a warm month, with an average temperature varying between 56.8°F (13.8°C) and 74.8°F (23.8°C). The commencement of September introduces an average high-temperature of a still moderately hot 74.8°F (23.8°C), closely mirroring the preceding month. Weather in September »Weather in October
October, the same as September, is another enjoyable autumn month in Wilmington, Illinois, with temperature in the range of an average low of 46°F (7.8°C) and an average high of 61.9°F (16.6°C). The beginning of October involves a decrease in the average high-temperature, transitioning from a moderately hot 74.8°F (23.8°C) in September to an enjoyable 61.9°F (16.6°C). Weather in October »Weather in November
The last month of the autumn, November, is also a frosty month in Wilmington, Illinois, with an average temperature ranging between max 47.3°F (8.5°C) and min 34.2°F (1.2°C). November's onset witnesses a marked shift in the average high-temperature, moving from a refreshing 61.9°F (16.6°C) in October to a chilly 47.3°F (8.5°C). Weather in November »Weather in December
December, the first month of the winter in Wilmington, is also a wintry month, with temperature in the range of an average high of 35.6°F (2°C) and an average low of 25.5°F (-3.6°C). The shift from November to December involves a decrease in the average high-temperature, from a frosty 47.3°F (8.5°C) to a wintry 35.6°F (2°C). Weather in December »Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature
Wilmington, IL
The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (29.7°F).
The month with the highest average low temperature is July (64.6°F).
The coldest month (with the lowest average low temperature) is January (17.8°F).
Average pressure
Wilmington, IL
- Average pressure in January:
30.12"Hg - Average pressure in February:
30.1"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:
29.92"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:
30.01"Hg - Average pressure in November:
30.1"Hg - Average pressure in December:
30.1"Hg
The month with the highest atmospheric pressure is January (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed
Wilmington, IL
- Average wind speed in January:
9.9mph - Average wind speed in February:
9.7mph - Average wind speed in March:
9.6mph - Average wind speed in April:
9.9mph - Average wind speed in May:
8.5mph - Average wind speed in June:
7.3mph
- Average wind speed in July:
6.2mph - Average wind speed in August:
6mph - Average wind speed in September:
7mph - Average wind speed in October:
8.8mph - Average wind speed in November:
9.4mph - Average wind speed in December:
9.3mph
The windiest months (with the highest average wind speed) are January and April (9.9mph).
The calmest month (with the lowest average wind speed) is August (6mph).
Average humidity
Wilmington, IL
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (72%).
Average rainfall
Wilmington, IL
- Average rainfall in January:
1.73" - Average rainfall in February:
1.69" - Average rainfall in March:
2.2" - Average rainfall in April:
3.74" - Average rainfall in May:
4.57" - Average rainfall in June:
3.98"
- Average rainfall in July:
3.58" - Average rainfall in August:
2.95" - Average rainfall in September:
2.52" - Average rainfall in October:
3.03" - Average rainfall in November:
1.69" - Average rainfall in December:
1.81"
The wettest month (with the highest rainfall) is May (4.57").
The driest months (with the least rainfall) are February and November (1.69").
Average rainfall days
Wilmington, IL
- Average rainfall days in January:
5.8 days - Average rainfall days in February:
6 days - Average rainfall days in March:
12.8 days - Average rainfall days in April:
17.3 days - Average rainfall days in May:
19.2 days - Average rainfall days in June:
18.8 days
- Average rainfall days in July:
19 days - Average rainfall days in August:
17 days - Average rainfall days in September:
13.2 days - Average rainfall days in October:
12.7 days - Average rainfall days in November:
9.9 days - Average rainfall days in December:
8.7 days
The month with the highest number of rainy days is May (19.2 days).
The month with the least rainy days is January (5.8 days).
Average snowfall
Wilmington, IL
The month with the highest snowfall is February (4.29").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days
Wilmington, IL
- Average snowfall days in January:
10.6 days - Average snowfall days in February:
9.7 days - Average snowfall days in March:
5.3 days - Average snowfall days in April:
1.8 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:
0.3 days - Average snowfall days in November:
2.5 days - Average snowfall days in December:
8.5 days
The month with the highest number of snowfall days is January (10.6 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight / Average sunshine
Wilmington, IL
- Average daylight in January:
9h and 36min - Average daylight in February:
10h and 36min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 24min - Average daylight in May:
14h and 30min - Average daylight in June:
15h and 6min
- Average daylight in July:
14h and 48min - Average daylight in August:
13h and 48min - Average daylight in September:
12h and 30min - Average daylight in October:
11h and 6min - Average daylight in November:
9h and 54min - Average daylight in December:
9h and 18min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in January:
3h and 54min - Average sunshine in February:
4h and 0min - Average sunshine in March:
6h and 12min - Average sunshine in April:
7h and 48min - Average sunshine in May:
8h and 48min - Average sunshine in June:
9h and 48min
- Average sunshine in July:
9h and 48min - Average sunshine in August:
9h and 48min - Average sunshine in September:
8h and 42min - Average sunshine in October:
6h and 0min - Average sunshine in November:
5h and 12min - Average sunshine in December:
4h and 18min
The months with the most sunshine are June, July and August (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).
Average sunshine days
Wilmington, IL
- Average sunshine days in January:
15.4 days - Average sunshine days in February:
13.4 days - Average sunshine days in March:
13.2 days - Average sunshine days in April:
10.3 days - Average sunshine days in May:
9.4 days - Average sunshine days in June:
9.6 days
- Average sunshine days in July:
8.6 days - Average sunshine days in August:
9.4 days - Average sunshine days in September:
14 days - Average sunshine days in October:
15.7 days - Average sunshine days in November:
17.2 days - Average sunshine days in December:
16 days
The month with the most sunshine days is November (17.2 days).
The month with the least sunshine days is July (8.6 days).
Average UV index
Wilmington, IL
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover
Wilmington, IL
The month with the most cloud cover is January (Cloud cover 60).
The months with the least cloud cover are August and September (Cloud cover 33).
Average visibility
Wilmington, IL
The months with the highest visibility are January, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are February, July and August (5mi).





