Climate and monthly weather forecastHarristown, IL
Climate and monthly weather forecast
Weather in January
January, like December, in Harristown, Illinois, is another cold winter month, with an average temperature ranging between min 21.2°F (-6°C) and max 32.9°F (0.5°C). Harristown, Illinois, witnesses the coldest weather in January, with temperatures averaging a high of 32.9°F (0.5°C) and a low of 21.2°F (-6°C). Weather in January »Weather in February
February, the last month of the winter in Harristown, is also a wintry month, with temperature in the range of an average low of 25.2°F (-3.8°C) and an average high of 37.8°F (3.2°C). Harristown's average high-temperature in February sits at a still cold 37.8°F (3.2°C), showing little difference from the previous month. Weather in February »Weather in March
The first month of the spring, March, is a cool month in Harristown, Illinois, with an average temperature fluctuating between 50.5°F (10.3°C) and 35.6°F (2°C). March's arrival is marked by an increase in the average high-temperature, moving from a wintry 37.8°F (3.2°C) in February to a cool 50.5°F (10.3°C). Weather in March »Weather in April
April in Harristown, Illinois, is a refreshing spring month, with an average temperature ranging between min 46°F (7.8°C) and max 61.9°F (16.6°C). April shows a rise in the average high-temperature, moving from March's fresh 50.5°F (10.3°C) to a refreshing 61.9°F (16.6°C). Weather in April »Weather in May
The last month of the spring, May, is an agreeable month in Harristown, Illinois, with temperature in the range of an average low of 56.7°F (13.7°C) and an average high of 72.9°F (22.7°C). The start of May brings a rise in the average high-temperature, moving from a comfortable 61.9°F (16.6°C) in April to a pleasant 72.9°F (22.7°C). Weather in May »Weather in June
The first month of the summer, June, is a moderately hot month in Harristown, Illinois, with an average temperature varying between 80.6°F (27°C) and 64°F (17.8°C). With the start of June, the average high-temperature marginally shifts from May's pleasant 72.9°F (22.7°C) to a moderately hot 80.6°F (27°C). Weather in June »Weather in July
July, like June, in Harristown, Illinois, is another warm summer month, with an average temperature ranging between min 65.7°F (18.7°C) and max 82°F (27.8°C). July tends to be the warmest month, with temperatures averaging a daily high of 82°F (27.8°C) and a low of 65.7°F (18.7°C). The heat index value during July is appraised at a tropical 89.6°F (32°C). Weather in July »Weather in August
August, the last month of the summer in Harristown, is also a moderately hot month, with an average temperature varying between 63.9°F (17.7°C) and 81.1°F (27.3°C). Transitioning into August, Harristown experiences an average high-temperature of a still warm 81.1°F (27.3°C), marking a minor shift from the preceding month. Weather in August »Weather in September
The first month of the autumn, September, is also a moderately hot month in Harristown, Illinois, with an average temperature fluctuating between 77°F (25°C) and 58.5°F (14.7°C). The beginning of September records an average high-temperature of a still warm 77°F (25°C), marking a negligible difference from August's 81.1°F (27.3°C). Weather in September »Weather in October
October, like September, in Harristown, Illinois, is another enjoyable autumn month, with an average temperature fluctuating between 64°F (17.8°C) and 48°F (8.9°C). In the transition to October, Harristown observes a drop in the average high-temperature, moving from a moderately hot 77°F (25°C) in September to a comfortable 64°F (17.8°C). Weather in October »Weather in November
November, the last month of the autumn in Harristown, is another chilly month, with an average temperature ranging between min 36.1°F (2.3°C) and max 49.8°F (9.9°C). A change in temperatures is noted as October gives way to November, with average highs reducing from a comfortable 64°F (17.8°C) to a chilly 49.8°F (9.9°C). Weather in November »Weather in December
December, the first month of the winter in Harristown, is still a cold month, with an average temperature ranging between max 38.5°F (3.6°C) and min 27.9°F (-2.3°C). A shift in the average high-temperature occurs in December, reducing from a frosty 49.8°F (9.9°C) in November to an icy 38.5°F (3.6°C). Weather in December »Updated: Aug 27, 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
January is the coldest month, exhibiting average temperatures of 32.9°F (0.5°C) at the peak and 21.2°F (-6°C) at the base.
In Harristown, during the entire year, the rain falls for 130.2 days and collects up to 16.34" (415mm) of precipitation.
Months with snowfall are January through April, November and December.
The month with the most snowfall is January, when snow falls for 7.2 days and typically aggregates up to 1.85" (47mm) of snow.
Throughout the year, there are 23.1 snowfall days, and 5.67" (144mm) of snow is accumulated.
January has the least sunshine of the year, with an average of 4.1h of sunshine.
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index.
February and December are months with the least rain when the rain falls for 5.8 days and typically aggregates up to 0.87" (22mm) of rain.
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.
May is the month with the most rainfall. Rain falls for 17 days and accumulates 2.01" (51mm) of precipitation.
May through October are months without snowfall.
With an average of 15h and 0min of daylight, June has the longest days of the year.
The month with the most sunshine is June, with an average of 10.4h of sunshine.
June through August, with an average maximum UV index of 6, are months with the highest UV index.
Harristown notes the warmest temperatures in July, with a average high of 82°F (27.8°C) and a low of 65.7°F (18.7°C).
July is the most humid month, with an average relative humidity of 84%.
With an average relative humidity of 70%, October is the least humid month.
With an average of 9h and 24min of daylight, December has the shortest days of the year.
Average temperature
Harristown, IL
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (32.9°F).
The month with the highest average low temperature is July (65.7°F).
The coldest month (with the lowest average low temperature) is January (21.2°F).
Average pressure
Harristown, IL
- Average pressure in January:
30.15"Hg - Average pressure in February:
30.12"Hg - Average pressure in March:
30.08"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:
30.03"Hg - Average pressure in October:
30.03"Hg - Average pressure in November:
30.12"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 (29.92"Hg).
Average wind speed
Harristown, 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:
10.6mph - Average wind speed in May:
8.8mph - Average wind speed in June:
7.5mph
- Average wind speed in July:
6.3mph - Average wind speed in August:
6.3mph - Average wind speed in September:
7.2mph - Average wind speed in October:
9.4mph - Average wind speed in November:
10.1mph - Average wind speed in December:
10.1mph
The windiest month (with the highest average wind speed) is January (10.7mph).
The calmest months (with the lowest average wind speed) are July and August (6.3mph).
Average humidity
Harristown, IL
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (70%).
Average rainfall
Harristown, IL
- Average rainfall in January:
1.06" - Average rainfall in February:
0.87" - Average rainfall in March:
1.3" - Average rainfall in April:
1.93" - Average rainfall in May:
2.01" - Average rainfall in June:
1.93"
- Average rainfall in July:
1.54" - Average rainfall in August:
1.5" - Average rainfall in September:
1.18" - Average rainfall in October:
1.22" - Average rainfall in November:
0.94" - Average rainfall in December:
0.87"
The wettest month (with the highest rainfall) is May (2.01").
The driest months (with the least rainfall) are February and December (0.87").
Average rainfall days
Harristown, IL
- Average rainfall days in January:
6.3 days - Average rainfall days in February:
5.8 days - Average rainfall days in March:
11.6 days - Average rainfall days in April:
13.6 days - Average rainfall days in May:
17 days - Average rainfall days in June:
13.7 days
- Average rainfall days in July:
14.8 days - Average rainfall days in August:
11.8 days - Average rainfall days in September:
10.6 days - Average rainfall days in October:
9.5 days - Average rainfall days in November:
8.4 days - Average rainfall days in December:
7.1 days
The month with the highest number of rainy days is May (17 days).
The month with the least rainy days is February (5.8 days).
Average snowfall
Harristown, IL
The month with the highest snowfall is January (1.85").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days
Harristown, IL
- Average snowfall days in January:
7.2 days - Average snowfall days in February:
5.9 days - Average snowfall days in March:
2.6 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:
1.6 days - Average snowfall days in December:
5.3 days
The month with the highest number of snowfall days is January (7.2 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight / Average sunshine
Harristown, IL
- Average daylight in January:
9h and 42min - 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:
15h and 0min
- Average daylight in July:
14h and 42min - 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: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in January:
4h and 6min - Average sunshine in February:
4h and 18min - Average sunshine in March:
6h and 24min - Average sunshine in April:
8h and 12min - Average sunshine in May:
9h and 18min - Average sunshine in June:
10h and 24min
- Average sunshine in July:
10h and 6min - Average sunshine in August:
9h and 54min - Average sunshine in September:
9h and 12min - Average sunshine in October:
6h and 18min - Average sunshine in November:
5h and 24min - Average sunshine in December:
4h and 36min
The month with the most sunshine is June (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days
Harristown, IL
- Average sunshine days in January:
19.5 days - Average sunshine days in February:
16.7 days - Average sunshine days in March:
16.4 days - Average sunshine days in April:
14.5 days - Average sunshine days in May:
11.5 days - Average sunshine days in June:
13 days
- Average sunshine days in July:
13.3 days - Average sunshine days in August:
16.6 days - Average sunshine days in September:
17.3 days - Average sunshine days in October:
19.8 days - Average sunshine days in November:
19.6 days - Average sunshine days in December:
19.4 days
The month with the most sunshine days is October (19.8 days).
The month with the least sunshine days is May (11.5 days).
Average UV index
Harristown, 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
Harristown, IL
The month with the most cloud cover is January (Cloud cover 56).
The month with the least cloud cover is September (Cloud cover 29).
Average visibility
Harristown, 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).
