Climate and monthly weather forecastDennison, IL
Climate and monthly weather forecast
Weather in January
January, like December, in Dennison, Illinois, is another cold winter month, with an average temperature fluctuating between 34.3°F (1.3°C) and 22.3°F (-5.4°C). Dennison's January weather, with an average high temperature of 34.3°F (1.3°C) and an average low temperature of 22.3°F (-5.4°C), tends to be the coldest of the year. Weather in January »Weather in February
The last month of the winter, February, is also a wintry month in Dennison, Illinois, with an average temperature varying between 39.4°F (4.1°C) and 26.1°F (-3.3°C). The transition from January to February sees average high-temperatures adjusting to a still cold 39.4°F (4.1°C), from a not significantly different 34.3°F (1.3°C). Weather in February »Weather in March
March, the first month of the spring in Dennison, is a cool month, with an average temperature varying between 36.1°F (2.3°C) and 51.4°F (10.8°C). The start of March brings a shift in the average high-temperature, increasing from February's cold 39.4°F (4.1°C) to a fresh 51.4°F (10.8°C). Weather in March »Weather in April
April is a refreshing spring month in Dennison, Illinois, with an average temperature fluctuating between 62.4°F (16.9°C) and 46°F (7.8°C). April's arrival signals a temperature shift, moving from a cool 51.4°F (10.8°C) in March to a comfortable 62.4°F (16.9°C). Weather in April »Weather in May
May, the last month of the spring in Dennison, is an agreeable month, with an average temperature varying between 73°F (22.8°C) and 55.9°F (13.3°C). May indicates a change in the average high-temperature, moving up from a comfortable 62.4°F (16.9°C) in April to an agreeable 73°F (22.8°C). Weather in May »Weather in June
The first month of the summer, June, is a warm month in Dennison, Illinois, with an average temperature varying between 81°F (27.2°C) and 63.9°F (17.7°C). Dennison's transition into June brings a slight rise in the average high-temperature, moving from an agreeable 73°F (22.8°C) in May to a moderately hot 81°F (27.2°C). Weather in June »Weather in July
July, like June, in Dennison, Illinois, is another warm summer month, with temperature in the range of an average high of 82.8°F (28.2°C) and an average low of 65.8°F (18.8°C). The average temperatures reach their apex in July, averaging 82.8°F (28.2°C) at the high end and 65.8°F (18.8°C) at the low end. The average heat index in July is computed to be a hot 91.4°F (33°C). Weather in July »Weather in August
August, the last month of the summer in Dennison, is another warm month, with an average temperature varying between 81.7°F (27.6°C) and 64°F (17.8°C). August brings an average high-temperature of a still warm 81.7°F (27.6°C), showing a slight difference from July's 82.8°F (28.2°C). Weather in August »Weather in September
September, the first month of the autumn in Dennison, is still a warm month, with an average temperature fluctuating between 77.4°F (25.2°C) and 58.6°F (14.8°C). The advent of September brings an average high-temperature of a still warm 77.4°F (25.2°C), almost identical to the preceding month. Weather in September »Weather in October
October, the same as September, is another enjoyable autumn month in Dennison, Illinois, with an average temperature ranging between max 64.6°F (18.1°C) and min 47.7°F (8.7°C). The onset of October coincides with a reduction in the average high-temperature, falling from a warm 77.4°F (25.2°C) in September to a comfortable 64.6°F (18.1°C). Weather in October »Weather in November
The last month of the autumn, November, is also a fresh month in Dennison, Illinois, with temperature in the range of an average high of 50.4°F (10.2°C) and an average low of 36.3°F (2.4°C). November shows a mild decline in the average high-temperature, falling from October's refreshing 64.6°F (18.1°C) to a cool 50.4°F (10.2°C). Weather in November »Weather in December
December, the first month of the winter in Dennison, is still a cold month, with an average temperature ranging between max 39.6°F (4.2°C) and min 28.4°F (-2°C). A shift in Dennison's weather is observed as November turns into December, with the average high temperature reducing from a cool 50.4°F (10.2°C) to a cold 39.6°F (4.2°C). Weather in December »Updated: Aug 2, 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 Dennison, January is the coldest month, with temperatures averaging a high of 34.3°F (1.3°C) and a low of 22.3°F (-5.4°C).
Throughout the year, there are 159.3 rainfall days, and 34.41" (874mm) of precipitation is accumulated.
Months with snowfall are January through April, November and December.
January is the month with the most snowfall. Snow falls for 7.8 days and accumulates 2.56" (65mm) of snow.
Throughout the year, there are 24.7 snowfall days, and 8.66" (220mm) of snow is accumulated.
The months with the least sunshine are January and December, with an average of 4.3h of sunshine.
January, February, October through December, with an average maximum UV index of 2, are months with the lowest UV index.
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.
April is the month with the most rainfall. Rain falls for 16 days and accumulates 4.96" (126mm) of precipitation.
In Dennison, snow does not fall in May through October.
June has the longest days of the year, with an average of 14h and 54min of daylight.
With an average of 10.2h of sunshine, June has the most sunshine of the year.
The months with the highest UV index are June through August, with an average maximum UV index of 6.
The month of July sees the average highest temperatures, reaching 82.8°F (28.2°C) at the peak and 65.8°F (18.8°C) at the low.
The most humid month is July, with an average relative humidity of 82%.
The month with the least rainfall is September, when the rain falls for 12.5 days and typically collects 1.81" (46mm) of precipitation.
With an average relative humidity of 72%, October is the least humid month in Dennison.
The month with the shortest days is December, with an average of 9h and 24min of daylight.
Average temperature
Dennison, IL
The warmest month (with the highest average high temperature) is July (82.8°F).
The month with the lowest average high temperature is January (34.3°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 (22.3°F).
Average pressure
Dennison, 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:
29.97"Hg - Average pressure in June:
29.93"Hg
- Average pressure in July:
29.98"Hg - Average pressure in August:
29.99"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
Dennison, IL
- Average wind speed in January:
10mph - Average wind speed in February:
10.1mph - Average wind speed in March:
9.9mph - Average wind speed in April:
9.9mph - Average wind speed in May:
8.2mph - Average wind speed in June:
7.1mph
- Average wind speed in July:
6mph - Average wind speed in August:
6mph - Average wind speed in September:
6.8mph - Average wind speed in October:
8.6mph - Average wind speed in November:
9.3mph - Average wind speed in December:
9.2mph
The windiest month (with the highest average wind speed) is February (10.1mph).
The calmest months (with the lowest average wind speed) are July and August (6mph).
Average humidity
Dennison, IL
The month with the highest relative humidity is July (82%).
The month with the lowest relative humidity is October (72%).
Average rainfall
Dennison, IL
- Average rainfall in January:
2.44" - Average rainfall in February:
1.93" - Average rainfall in March:
2.76" - Average rainfall in April:
4.96" - Average rainfall in May:
4.06" - Average rainfall in June:
3.94"
- Average rainfall in July:
3.11" - Average rainfall in August:
2.56" - Average rainfall in September:
1.81" - Average rainfall in October:
2.44" - Average rainfall in November:
2.09" - Average rainfall in December:
2.32"
The wettest month (with the highest rainfall) is April (4.96").
The driest month (with the least rainfall) is September (1.81").
Average rainfall days
Dennison, IL
- Average rainfall days in January:
8.2 days - Average rainfall days in February:
8.7 days - Average rainfall days in March:
13.8 days - Average rainfall days in April:
16 days - Average rainfall days in May:
20.6 days - Average rainfall days in June:
17 days
- Average rainfall days in July:
17.7 days - Average rainfall days in August:
14.6 days - Average rainfall days in September:
12.5 days - Average rainfall days in October:
11.3 days - Average rainfall days in November:
9.4 days - Average rainfall days in December:
9.5 days
The month with the highest number of rainy days is May (20.6 days).
The month with the least rainy days is January (8.2 days).
Average snowfall
Dennison, IL
The month with the highest snowfall is January (2.56").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days
Dennison, IL
- Average snowfall days in January:
7.8 days - Average snowfall days in February:
5.8 days - Average snowfall days in March:
3.3 days - Average snowfall days in April:
0.5 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 days - Average snowfall days in November:
1.8 days - Average snowfall days in December:
5.5 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, September and October (0 days).
Average daylight / Average sunshine
Dennison, 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 18min - Average sunshine in February:
5h and 30min - Average sunshine in March:
6h and 18min - Average sunshine in April:
6h and 54min - Average sunshine in May:
8h and 30min - Average sunshine in June:
10h and 12min
- Average sunshine in July:
9h and 54min - Average sunshine in August:
9h and 6min - Average sunshine in September:
8h and 24min - Average sunshine in October:
7h and 0min - Average sunshine in November:
5h and 12min - Average sunshine in December:
4h and 18min
The month with the most sunshine is June (Average sunshine: 10h and 12min).
The months with the least sunshine are January and December (Average sunshine: 4h and 18min).
Average sunshine days
Dennison, IL
- Average sunshine days in January:
16.1 days - Average sunshine days in February:
13.4 days - Average sunshine days in March:
13.4 days - Average sunshine days in April:
12.2 days - Average sunshine days in May:
7.9 days - Average sunshine days in June:
10.9 days
- Average sunshine days in July:
10.3 days - Average sunshine days in August:
13.5 days - Average sunshine days in September:
15.7 days - Average sunshine days in October:
17.7 days - Average sunshine days in November:
18.4 days - Average sunshine days in December:
17.2 days
The month with the most sunshine days is November (18.4 days).
The month with the least sunshine days is May (7.9 days).
Average UV index
Dennison, 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, October, November and December (UV index 2).
Average cloud cover
Dennison, IL
The month with the most cloud cover is January (Cloud cover 57).
The months with the least cloud cover are June, August and September (Cloud cover 32).
Average visibility
Dennison, 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).
