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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, the same as December, in Janesville, Iowa, is a freezing cold winter month, with temperature in the range of an average low of 11.3°F (-11.5°C) and an average high of 23.9°F (-4.5°C). With average high and low temperatures of 23.9°F (-4.5°C) and 11.3°F (-11.5°C) respectively, January is Janesville's coldest month. Weather in January »
Weather in February
The last month of the winter, February, is another freezing cold month in Janesville, Iowa, with an average temperature varying between 14.5°F (-9.7°C) and 27.7°F (-2.4°C). The beginning of February records an average high-temperature of a still subzero cold 27.7°F (-2.4°C), almost echoing the conditions of the previous month. Weather in February »
Weather in March
The first month of the spring, March, is a frosty month in Janesville, Iowa, with temperature in the range of an average high of 43°F (6.1°C) and an average low of 28.9°F (-1.7°C). With the onset of March, Janesville's average high-temperature witnesses a clear rise, advancing from February's subzero cold 27.7°F (-2.4°C) to a frosty 43°F (6.1°C). Weather in March »
Weather in April
April is a moderate spring month in Janesville, Iowa, with an average temperature fluctuating between 56.1°F (13.4°C) and 39.7°F (4.3°C). April sees a rise in the average high-temperature, climbing from a frosty 43°F (6.1°C) in March to a moderate 56.1°F (13.4°C). Weather in April »
Weather in May
The last month of the spring, May, is a refreshing month in Janesville, Iowa, with an average temperature ranging between min 51.4°F (10.8°C) and max 67.8°F (19.9°C). Janesville sees an increase in the average high-temperature with the arrival of May, moving from April's refreshing 56.1°F (13.4°C) to an enjoyable 67.8°F (19.9°C). Weather in May »
Weather in June
The first month of the summer, June, is a moderately hot month in Janesville, Iowa, with an average temperature varying between 60.8°F (16°C) and 77°F (25°C). The commencement of June sees a shift in the average high-temperature, moving from a refreshing 67.8°F (19.9°C) in May to a warm 77°F (25°C). Weather in June »
Weather in July
July, like June, in Janesville, Iowa, is another warm summer month, with an average temperature varying between 63°F (17.2°C) and 79.5°F (26.4°C). In Janesville, July records the highest average temperatures, peaking at 79.5°F (26.4°C) and reaching a low of 63°F (17.2°C). Weather in July »
Weather in August
The last month of the summer, August, is another warm month in Janesville, Iowa, with an average temperature varying between 78.3°F (25.7°C) and 60.4°F (15.8°C). Janesville experiences a transition to a still warm 78.3°F (25.7°C) in average high-temperatures with the arrival of August, not greatly differing from July's 79.5°F (26.4°C). Weather in August »
Weather in September
September, the first month of the autumn in Janesville, is also an agreeable month, with an average temperature fluctuating between 54°F (12.2°C) and 72.9°F (22.7°C). September is characterized by a mild reduction in the average high-temperature, from a moderately hot 78.3°F (25.7°C) in August to an agreeable 72.9°F (22.7°C). Weather in September »
Weather in October
October, like September, is another mild autumn month in Janesville, Iowa, with an average temperature varying between 43°F (6.1°C) and 58.1°F (14.5°C). As September transitions into October, Janesville sees a clear drop in the average high-temperature, declining from a pleasant 72.9°F (22.7°C) to a mild 58.1°F (14.5°C). Weather in October »
Weather in November
November, the last month of the autumn in Janesville, is another chilly month, with an average temperature fluctuating between 43.5°F (6.4°C) and 30.9°F (-0.6°C). Janesville's weather experiences a significant temperature drop with the arrival of November, falling from a mild 58.1°F (14.5°C) in October to a frosty 43.5°F (6.4°C). Weather in November »
Weather in December
The first month of the winter, December, is also a subzero cold month in Janesville, Iowa, with an average temperature ranging between max 30.2°F (-1°C) and min 19.8°F (-6.8°C). In Janesville, the average high-temperature in December drops from a chilly 43.5°F (6.4°C) in November to a subzero cold 30.2°F (-1°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
What month is the coldest?
Janesville's January weather reaches an average high of 23.9°F (-4.5°C) and an average low of 11.3°F (-11.5°C), making it the coldest month.
What is the most humid month?
With an average relative humidity of 87%, January is the most humid month.
What is the driest month?
The month with the least rainfall is January, when the rain falls for 4.2 days and typically collects 1.02" (26mm) of precipitation.
How many days does it rain?
In Janesville, during the entire year, the rain falls for 138.7 days and collects up to 28.78" (731mm) of precipitation.
When does it snow?
January through May, October through December are months with snowfall.
How many days does it snow?
Throughout the year, there are 43.6 snowfall days, and 19.25" (489mm) of snow is accumulated.
What is the month with the least sunshine in Janesville?
January has the least sunshine of the year, with an average of 3.8h of sunshine.
What is the month with the lowest UV index?
The months with the lowest UV index are January and December, with an average maximum UV index of 1.
When does it snow the most?
The month with the most snowfall is February, when snow falls for 10 days and typically aggregates up to 5.08" (129mm) of snow.
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 wettest month?
The month with the most rainfall is June, when the rain falls for 19.4 days and typically aggregates up to 4.29" (109mm) of precipitation.
When it does not snow?
In Janesville, snow does not fall in June through September.
When are the longest days?
June has the longest days of the year, with an average of 15h and 18min of daylight.
What is the month with the highest UV index?
The month with the highest UV index is June, with an average maximum UV index of 6.
What is the hottest time of year?
During the warmest month in Janesville, July, temperatures average a high of 79.5°F (26.4°C) and a low of 63°F (17.2°C).
What month has the most sunshine?
July has the most sunshine of the year, with an average of 9.9h of sunshine.
What is the least humid month?
October is the least humid month, with an average relative humidity of 72%.
What is the month with the shortest days?
December has the shortest days of the year, with an average of 9h and 6min of daylight.
Average temperature
Janesville, IA
The warmest month (with the highest average high temperature) is July (79.5°F).
The month with the lowest average high temperature is January (23.9°F).
The month with the highest average low temperature is July (63°F).
The coldest month (with the lowest average low temperature) is January (11.3°F).
Average pressure
Janesville, IA
- Average pressure in January:
30.14"Hg - Average pressure in February:
30.13"Hg - Average pressure in March:
30.08"Hg - Average pressure in April:
29.93"Hg - Average pressure in May:
29.94"Hg - Average pressure in June:
29.89"Hg
- Average pressure in July:
29.96"Hg - Average pressure in August:
29.96"Hg - Average pressure in September:
30.02"Hg - Average pressure in October:
30"Hg - Average pressure in November:
30.08"Hg - Average pressure in December:
30.11"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed
Janesville, IA
- Average wind speed in January:
10.5mph - Average wind speed in February:
10.4mph - Average wind speed in March:
10.4mph - Average wind speed in April:
10.7mph - Average wind speed in May:
9.2mph - Average wind speed in June:
8.1mph
- Average wind speed in July:
7.1mph - Average wind speed in August:
7mph - Average wind speed in September:
8.2mph - Average wind speed in October:
9.8mph - Average wind speed in November:
10.4mph - Average wind speed in December:
10mph
The windiest month (with the highest average wind speed) is April (10.7mph).
The calmest month (with the lowest average wind speed) is August (7mph).
Average humidity
Janesville, IA
The month with the highest relative humidity is January (87%).
The month with the lowest relative humidity is October (72%).
Average rainfall
Janesville, IA
- Average rainfall in January:
1.02" - Average rainfall in February:
1.18" - Average rainfall in March:
1.69" - Average rainfall in April:
3.11" - Average rainfall in May:
4.17" - Average rainfall in June:
4.29"
- Average rainfall in July:
2.95" - Average rainfall in August:
2.36" - Average rainfall in September:
2.4" - Average rainfall in October:
2.68" - Average rainfall in November:
1.38" - Average rainfall in December:
1.54"
The wettest month (with the highest rainfall) is June (4.29").
The driest month (with the least rainfall) is January (1.02").
Average rainfall days
Janesville, IA
- Average rainfall days in January:
4.2 days - Average rainfall days in February:
3.9 days - Average rainfall days in March:
9.6 days - Average rainfall days in April:
14.7 days - Average rainfall days in May:
18.7 days - Average rainfall days in June:
19.4 days
- Average rainfall days in July:
16.3 days - Average rainfall days in August:
14.5 days - Average rainfall days in September:
12.8 days - Average rainfall days in October:
10.7 days - Average rainfall days in November:
8.2 days - Average rainfall days in December:
5.7 days
The month with the highest number of rainy days is June (19.4 days).
The month with the least rainy days is February (3.9 days).
Average snowfall
Janesville, IA
- Average snowfall in January:
4.33" - Average snowfall in February:
5.08" - Average snowfall in March:
2.36" - Average snowfall in April:
1.89" - Average snowfall in May:
0.2" - Average snowfall in June:
0"
The month with the highest snowfall is February (5.08").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days
Janesville, IA
- Average snowfall days in January:
10.5 days - Average snowfall days in February:
10 days - Average snowfall days in March:
6.3 days - Average snowfall days in April:
2.1 days - Average snowfall days in May:
0.2 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:
1.2 days - Average snowfall days in November:
3.8 days - Average snowfall days in December:
9.5 days
The month with the highest number of snowfall days is January (10.5 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
Janesville, IA
- Average daylight in January:
9h and 3min - 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 4min - Average daylight in June:
15h and 2min
- Average daylight in July:
14h and 5min - Average daylight in August:
13h and 5min - Average daylight in September:
12h and 3min - Average daylight in October:
11h and 0min - Average daylight in November:
9h and 5min - Average daylight in December:
9h and 1min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in January:
3h and 5min - Average sunshine in February:
4h and 0min - Average sunshine in March:
6h and 0min - Average sunshine in April:
7h and 3min - Average sunshine in May:
8h and 3min - Average sunshine in June:
9h and 4min
- Average sunshine in July:
9h and 5min - Average sunshine in August:
9h and 5min - Average sunshine in September:
9h and 1min - Average sunshine in October:
5h and 2min - Average sunshine in November:
5h and 1min - Average sunshine in December:
4h and 2min
The month with the most sunshine is July (Average sunshine: 9h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days
Janesville, IA
- Average sunshine days in January:
17.2 days - Average sunshine days in February:
14.9 days - Average sunshine days in March:
15.4 days - Average sunshine days in April:
11.8 days - Average sunshine days in May:
10.3 days - Average sunshine days in June:
9.2 days
- Average sunshine days in July:
10.3 days - Average sunshine days in August:
13.1 days - Average sunshine days in September:
15.5 days - Average sunshine days in October:
17.8 days - Average sunshine days in November:
17.8 days - Average sunshine days in December:
17.6 days
The months with the most sunshine days are October and November (17.8 days).
The month with the least sunshine days is June (9.2 days).
Average UV index
Janesville, IA
The month with the highest UV index is June (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover
Janesville, IA
The month with the most cloud cover is January (Cloud cover 61).
The month with the least cloud cover is August (Cloud cover 31).
Average visibility
Janesville, IA
The months with the highest visibility are February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are January, July and August (5mi).
Janesville, Iowa, USA
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