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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 Sumner, Iowa, is another subzero cold winter month, with an average temperature varying between 11.1°F (-11.6°C) and 23.5°F (-4.7°C). Temperature readings reach their annual highs in January, averaging 23.5°F (-4.7°C) and a minimum average of 11.1°F (-11.6°C). Weather in January »
Weather in February
The last month of the winter, February, is another freezing cold month in Sumner, Iowa, with an average temperature varying between 14°F (-10°C) and 27°F (-2.8°C). February's arrival shows an average high-temperature of a still subzero cold 27°F (-2.8°C), hardly different from the previous month. Weather in February »
Weather in March
March, the first month of the spring in Sumner, is a wintry month, with temperature in the range of an average high of 42.4°F (5.8°C) and an average low of 28°F (-2.2°C). Witnessing a clear rise in March, the average high-temperature escalates from February's subzero cold 27°F (-2.8°C) to a cold 42.4°F (5.8°C). Weather in March »
Weather in April
April is a cool spring month in Sumner, Iowa, with an average temperature ranging between min 39°F (3.9°C) and max 55°F (12.8°C). As April arrives, Sumner's weather shows an increase in high-temperatures, moving from March's cold 42.4°F (5.8°C) to a fresh 55°F (12.8°C). Weather in April »
Weather in May
May, the last month of the spring in Sumner, is a refreshing month, with an average temperature fluctuating between 50.5°F (10.3°C) and 66.7°F (19.3°C). May indicates a change in the average high-temperature, moving up from a fresh 55°F (12.8°C) in April to a refreshing 66.7°F (19.3°C). Weather in May »
Weather in June
The first month of the summer, June, is a warm month in Sumner, Iowa, with an average temperature ranging between min 60.3°F (15.7°C) and max 76.5°F (24.7°C). With the onset of June, Sumner's average high-temperature sees a rise, moving from May's refreshing 66.7°F (19.3°C) to a warm 76.5°F (24.7°C). Weather in June »
Weather in July
July, like June, in Sumner, Iowa, is another warm summer month, with temperature in the range of an average low of 62.6°F (17°C) and an average high of 79.2°F (26.2°C). Sumner's warmest month, July, registers temperatures that range from a high of 79.2°F (26.2°C) to a low of 62.6°F (17°C). Weather in July »
Weather in August
The last month of the summer, August, is also a moderately hot month in Sumner, Iowa, with an average temperature ranging between max 77.7°F (25.4°C) and min 60.1°F (15.6°C). August's average high-temperature is a still moderately hot 77.7°F (25.4°C), maintaining a close comparison with July's 79.2°F (26.2°C). Weather in August »
Weather in September
The first month of the autumn, September, is also an agreeable month in Sumner, Iowa, with an average temperature varying between 71.8°F (22.1°C) and 53.4°F (11.9°C). Sumner's weather in September involves a mild decrease in the average high-temperature, moving down slightly from August's warm 77.7°F (25.4°C) to a pleasant 71.8°F (22.1°C). Weather in September »
Weather in October
October, the same as September, in Sumner, Iowa, is another refreshing autumn month, with an average temperature fluctuating between 42.4°F (5.8°C) and 57.7°F (14.3°C). The transition into October is accompanied by a temperature decrease, with the average high-temperature shifting from a pleasant 71.8°F (22.1°C) in September to a refreshing 57.7°F (14.3°C). Weather in October »
Weather in November
The last month of the autumn, November, is also a frosty month in Sumner, Iowa, with an average temperature ranging between min 30.4°F (-0.9°C) and max 43°F (6.1°C). The onset of November brings a distinct decrease in the average high-temperature, receding from a mild 57.7°F (14.3°C) in October to a frosty 43°F (6.1°C). Weather in November »
Weather in December
December, the first month of the winter in Sumner, is also a subzero cold month, with temperature in the range of an average high of 29.8°F (-1.2°C) and an average low of 19.4°F (-7°C). As December arrives, Sumner's weather displays a decrease in high-temperatures, transitioning from November's frosty 43°F (6.1°C) to a subzero cold 29.8°F (-1.2°C). Weather in December »
Updated: Jul 1, 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 time of the year is the coldest?
In Sumner, January is known for its average lowest temperatures, reaching a high of 23.5°F (-4.7°C) and a low of 11.1°F (-11.6°C).
What are the most humid months in Sumner?
The months with the highest humidity are January and February, with an average relative humidity of 88%.
What is the driest month?
January is the month with the least rainfall. Rain falls for 4.3 days and accumulates 1.14" (29mm) of precipitation.
How much does it rain?
Throughout the year, there are 146.8 rainfall days, and 30.79" (782mm) of precipitation is accumulated.
When does it snow?
January through May, October through December are months with snowfall.
How much does it snow?
Throughout the year, there are 55.9 snowfall days, and 23.46" (596mm) of snow is accumulated.
What is the month with the least sunshine?
January has the least sunshine of the year, with an average of 3.6h of sunshine.
When is 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?
February is the month with the most snowfall. Snow falls for 12.6 days and accumulates 5.83" (148mm) 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 rainiest month?
June is the month with the most rainfall. Rain falls for 20.2 days and accumulates 5.04" (128mm) of precipitation.
When it does not snow?
In Sumner, snow does not fall in June through September.
When are the longest days?
The month with the longest days is June, with an average of 15h and 18min of daylight.
When is the highest UV index?
June is the month with the highest UV index, with an average maximum UV index of 6.
What month is the hottest?
The warmest month is July, with an average high-temperature of 79.2°F (26.2°C) and an average low-temperature of 62.6°F (17°C).
What are the months with the most sunshine?
The months with the most sunshine are July and August, with an average of 9.8h of sunshine.
What is the least humid month?
With an average relative humidity of 73%, October is the least humid month.
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
Sumner, IA
The warmest month (with the highest average high temperature) is July (79.2°F).
The month with the lowest average high temperature is January (23.5°F).
The month with the highest average low temperature is July (62.6°F).
The coldest month (with the lowest average low temperature) is January (11.1°F).
Average pressure
Sumner, 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:
29.99"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
Sumner, IA
- Average wind speed in January:
10.6mph - Average wind speed in February:
10.5mph - Average wind speed in March:
10.4mph - Average wind speed in April:
10.8mph - Average wind speed in May:
9.3mph - Average wind speed in June:
8.1mph
- Average wind speed in July:
7.1mph - Average wind speed in August:
7.1mph - Average wind speed in September:
8.3mph - Average wind speed in October:
9.9mph - Average wind speed in November:
10.4mph - Average wind speed in December:
10.1mph
The windiest month (with the highest average wind speed) is April (10.8mph).
The calmest months (with the lowest average wind speed) are July and August (7.1mph).
Average humidity
Sumner, IA
The months with the highest relative humidity are January and February (88%).
The month with the lowest relative humidity is October (73%).
Average rainfall
Sumner, IA
- Average rainfall in January:
1.14" - Average rainfall in February:
1.26" - Average rainfall in March:
1.85" - Average rainfall in April:
3.43" - Average rainfall in May:
4.45" - Average rainfall in June:
5.04"
- Average rainfall in July:
3.07" - Average rainfall in August:
2.4" - Average rainfall in September:
2.28" - Average rainfall in October:
2.72" - Average rainfall in November:
1.54" - Average rainfall in December:
1.61"
The wettest month (with the highest rainfall) is June (5.04").
The driest month (with the least rainfall) is January (1.14").
Average rainfall days
Sumner, IA
- Average rainfall days in January:
4.3 days - Average rainfall days in February:
4.3 days - Average rainfall days in March:
10.9 days - Average rainfall days in April:
16.1 days - Average rainfall days in May:
20.3 days - Average rainfall days in June:
20.2 days
- Average rainfall days in July:
17.3 days - Average rainfall days in August:
14.5 days - Average rainfall days in September:
12.5 days - Average rainfall days in October:
11.4 days - Average rainfall days in November:
8.6 days - Average rainfall days in December:
6.4 days
The month with the highest number of rainy days is May (20.3 days).
The months with the least rainy days are January and February (4.3 days).
Average snowfall
Sumner, IA
- Average snowfall in January:
5.31" - Average snowfall in February:
5.83" - Average snowfall in March:
2.72" - Average snowfall in April:
1.77" - Average snowfall in May:
0.24" - Average snowfall in June:
0"
The month with the highest snowfall is February (5.83").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days
Sumner, IA
- Average snowfall days in January:
13.6 days - Average snowfall days in February:
12.6 days - Average snowfall days in March:
7.5 days - Average snowfall days in April:
3 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:
1.6 days - Average snowfall days in November:
4.9 days - Average snowfall days in December:
12.5 days
The month with the highest number of snowfall days is January (13.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
Sumner, 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:
15h and 0min - 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 4min - Average sunshine in February:
3h and 5min - Average sunshine in March:
6h and 0min - Average sunshine in April:
7h and 2min - Average sunshine in May:
8h and 2min - Average sunshine in June:
9h and 2min
- 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 1min
The months with the most sunshine are July and August (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 36min).
Average sunshine days
Sumner, IA
- Average sunshine days in January:
14 days - Average sunshine days in February:
12 days - Average sunshine days in March:
12.9 days - Average sunshine days in April:
10.3 days - Average sunshine days in May:
8.9 days - Average sunshine days in June:
7.3 days
- Average sunshine days in July:
9.8 days - Average sunshine days in August:
13.2 days - Average sunshine days in September:
15.4 days - Average sunshine days in October:
16.6 days - Average sunshine days in November:
16.8 days - Average sunshine days in December:
15.5 days
The month with the most sunshine days is November (16.8 days).
The month with the least sunshine days is June (7.3 days).
Average UV index
Sumner, 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
Sumner, IA
The month with the most cloud cover is January (Cloud cover 62).
The months with the least cloud cover are August and September (Cloud cover 32).
Average visibility
Sumner, IA
The months with the highest visibility are March, April, May, June, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February and July (5mi).
Sumner, Iowa, USA
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