Climate and monthly weather forecastWaterloo, IL
Climate and monthly weather forecast
Weather in January
January, like December, in Waterloo, Illinois, is an icy winter month, with an average temperature ranging between max 38.3°F (3.5°C) and min 25.2°F (-3.8°C). Waterloo's coldest month, January, generally records average temperatures ranging from a high of 38.3°F (3.5°C) to a low of 25.2°F (-3.8°C). Weather in January »Weather in February
February, the last month of the winter in Waterloo, is a chilly month, with an average temperature ranging between max 43.2°F (6.2°C) and min 28.4°F (-2°C). The advent of February reveals an average high-temperature of a frosty 43.2°F (6.2°C), showing minimal difference from the prior month. Weather in February »Weather in March
The first month of the spring, March, is a cool month in Waterloo, Illinois, with temperature in the range of an average low of 38.3°F (3.5°C) and an average high of 54.5°F (12.5°C). The shift from February to March is marked by an increase in the average high-temperature, moving from a frosty 43.2°F (6.2°C) to a cool 54.5°F (12.5°C). Weather in March »Weather in April
April is an enjoyable spring month in Waterloo, Illinois, with an average temperature varying between 47.8°F (8.8°C) and 65.7°F (18.7°C). Waterloo, Illinois, experiences a temperature shift with the start of April, with average high-temperatures moving from a fresh 54.5°F (12.5°C) in March to an enjoyable 65.7°F (18.7°C). Weather in April »Weather in May
May, the last month of the spring in Waterloo, is a moderately hot month, with an average temperature varying between 75°F (23.9°C) and 57.7°F (14.3°C). An escalation in the average high-temperature is seen with the onset of May, moving from an enjoyable 65.7°F (18.7°C) in April to a moderately hot 75°F (23.9°C). Weather in May »Weather in June
June, the first month of the summer in Waterloo, is still a warm month, with an average temperature ranging between min 66.6°F (19.2°C) and max 84.6°F (29.2°C). Waterloo sees a rise in temperature during June, with average high-temperatures transitioning from a moderately hot 75°F (23.9°C) in May to a still warm 84.6°F (29.2°C). Weather in June »Weather in July
July is a hot summer month in Waterloo, Illinois, with temperature in the range of an average high of 87.3°F (30.7°C) and an average low of 68.7°F (20.4°C). July, recognised by an average high temperature of 87.3°F (30.7°C) and a low of 68.7°F (20.4°C), is Waterloo's warmest month. July's heat index is computed to be a very hot 102.2°F (39°C). Weather in July »Weather in August
August, the last month of the summer in Waterloo, is another warm month, with temperature in the range of an average low of 66.6°F (19.2°C) and an average high of 85.1°F (29.5°C). August's beginning signals an average high-temperature of a moderately hot 85.1°F (29.5°C), barely different from July's 87.3°F (30.7°C). Weather in August »Weather in September
The first month of the autumn, September, is still a warm month in Waterloo, Illinois, with an average temperature ranging between min 60.3°F (15.7°C) and max 79.5°F (26.4°C). The shift from August to September coincides with a small decrease in the average high-temperature, down to a still warm 79.5°F (26.4°C) from 85.1°F (29.5°C). Weather in September »Weather in October
October, like September, in Waterloo, Illinois, is another enjoyable autumn month, with an average temperature ranging between max 66.7°F (19.3°C) and min 48.9°F (9.4°C). The commencement of October indicates a shift in the average high-temperature, receding from September's moderately hot 79.5°F (26.4°C) to a refreshing 66.7°F (19.3°C). Weather in October »Weather in November
The last month of the autumn, November, is also a fresh month in Waterloo, Illinois, with an average temperature fluctuating between 38.1°F (3.4°C) and 53.6°F (12°C). November's arrival correlates with a reduction in the average high-temperature, down from an enjoyable 66.7°F (19.3°C) in October to a fresh 53.6°F (12°C). Weather in November »Weather in December
The first month of the winter, December, is also a frosty month in Waterloo, Illinois, with an average temperature varying between 43.2°F (6.2°C) and 30.9°F (-0.6°C). In Waterloo, the beginning of December is marked by a lowered average high-temperature, shifting from November's cool 53.6°F (12°C) to a chilly 43.2°F (6.2°C). Weather in December »Updated: Feb 12, 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
Waterloo, Illinois, records the coldest temperatures in January, averaging a high of 38.3°F (3.5°C) and a low of 25.2°F (-3.8°C).
Throughout the year, in Waterloo, Illinois, there are 139.8 rainfall days, and 25.63" (651mm) of precipitation is accumulated.
Months with snowfall in Waterloo are January through March, September, November and December.
The month with the most snowfall is January, when snow falls for 6.3 days and typically aggregates up to 1.89" (48mm) of snow.
Throughout the year, there are 18.7 snowfall days, and 6.65" (169mm) of snow is accumulated.
January has the least sunshine of the year in Waterloo, Illinois, with an average of 4.7h of sunshine.
The months with the lowest UV index are January, February and December, with an average maximum UV index of 2.
February and November are months with the least rain in Waterloo, Illinois, when the rain falls for 7.5 days and typically aggregates up to 1.34" (34mm) of rain.
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts in Waterloo, 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 through August and October are months without snowfall in Waterloo.
May is the most humid month in Waterloo, with an average relative humidity of 79%.
May is the month with the most rainfall in Waterloo, Illinois. Rain falls for 15.4 days and accumulates 3.19" (81mm) of precipitation.
May through August, with an average maximum UV index of 6, are months with the highest UV index in Waterloo.
June has the longest days of the year in Waterloo, with an average of 14h and 48min of daylight.
The months with the most sunshine in Waterloo, Illinois, are June and July, with an average of 10.5h of sunshine.
Waterloo's warmest month, July, generally records average temperatures ranging from a high of 87.3°F (30.7°C) to a low of 68.7°F (20.4°C).
October is the least humid month in Waterloo, Illinois, with an average relative humidity of 71%.
With an average of 9h and 30min of daylight, December has the shortest days of the year.
Average temperature
Waterloo, IL
The warmest month (with the highest average high temperature) is July (87.3°F).
The month with the lowest average high temperature is January (38.3°F).
The month with the highest average low temperature is July (68.7°F).
The coldest month (with the lowest average low temperature) is January (25.2°F).
Average pressure
Waterloo, IL
- Average pressure in January:
30.16"Hg - Average pressure in February:
30.12"Hg - Average pressure in March:
30.07"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:
30.02"Hg - Average pressure in October:
30.04"Hg - Average pressure in November:
30.13"Hg - Average pressure in December:
30.13"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed
Waterloo, IL
- Average wind speed in January:
9.3mph - Average wind speed in February:
9.1mph - Average wind speed in March:
8.9mph - Average wind speed in April:
8.8mph - Average wind speed in May:
7.2mph - Average wind speed in June:
6.3mph
- Average wind speed in July:
5.5mph - Average wind speed in August:
5.5mph - Average wind speed in September:
5.8mph - Average wind speed in October:
7.7mph - Average wind speed in November:
8.3mph - Average wind speed in December:
8.5mph
The windiest month (with the highest average wind speed) is January (9.3mph).
The calmest months (with the lowest average wind speed) are July and August (5.5mph).
Average humidity
Waterloo, IL
The month with the highest relative humidity is May (79%).
The month with the lowest relative humidity is October (71%).
Average rainfall
Waterloo, IL
- Average rainfall in January:
1.46" - Average rainfall in February:
1.34" - Average rainfall in March:
1.97" - Average rainfall in April:
2.64" - Average rainfall in May:
3.19" - Average rainfall in June:
2.91"
- Average rainfall in July:
2.8" - Average rainfall in August:
2.76" - Average rainfall in September:
1.61" - Average rainfall in October:
1.85" - Average rainfall in November:
1.34" - Average rainfall in December:
1.77"
The wettest month (with the highest rainfall) is May (3.19").
The driest months (with the least rainfall) are February and November (1.34").
Average rainfall days
Waterloo, IL
- Average rainfall days in January:
6.3 days - Average rainfall days in February:
7.5 days - Average rainfall days in March:
12.8 days - Average rainfall days in April:
14.6 days - Average rainfall days in May:
15.4 days - Average rainfall days in June:
14.7 days
- Average rainfall days in July:
16.2 days - Average rainfall days in August:
13.8 days - Average rainfall days in September:
11.9 days - Average rainfall days in October:
9.5 days - Average rainfall days in November:
9 days - Average rainfall days in December:
8.1 days
The month with the highest number of rainy days is July (16.2 days).
The month with the least rainy days is January (6.3 days).
Average snowfall
Waterloo, IL
The month with the highest snowfall is January (1.89").
The months with the least snowfall are April, May, June, July, August and October (0").
Average snowfall days
Waterloo, IL
- Average snowfall days in January:
6.3 days - Average snowfall days in February:
5.1 days - Average snowfall days in March:
2 days - Average snowfall days in April:
0.3 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:
0.1 days - Average snowfall days in October:
0 days - Average snowfall days in November:
1.4 days - Average snowfall days in December:
3.5 days
The month with the highest number of snowfall days is January (6.3 days).
The months with the least snowfall days are May, June, July, August and October (0 days).
Average daylight / Average sunshine
Waterloo, IL
- Average daylight in January:
9h and 54min - Average daylight in February:
10h and 48min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 12min - Average daylight in May:
14h and 18min - Average daylight in June:
14h and 48min
- Average daylight in July:
14h and 30min - Average daylight in August:
13h and 36min - Average daylight in September:
12h and 24min - Average daylight in October:
11h and 12min - Average daylight in November:
10h and 6min - Average daylight in December:
9h and 30min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in January:
4h and 42min - Average sunshine in February:
4h and 54min - Average sunshine in March:
6h and 36min - Average sunshine in April:
8h and 36min - Average sunshine in May:
9h and 30min - Average sunshine in June:
10h and 30min
- Average sunshine in July:
10h and 30min - Average sunshine in August:
10h and 18min - Average sunshine in September:
9h and 30min - Average sunshine in October:
6h and 18min - Average sunshine in November:
5h and 36min - Average sunshine in December:
5h and 0min
The months with the most sunshine are June and July (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 4h and 42min).
Average sunshine days
Waterloo, IL
- Average sunshine days in January:
20.6 days - Average sunshine days in February:
16.3 days - Average sunshine days in March:
15 days - Average sunshine days in April:
14.9 days - Average sunshine days in May:
13.3 days - Average sunshine days in June:
12.9 days
- Average sunshine days in July:
12.5 days - Average sunshine days in August:
14.9 days - Average sunshine days in September:
15.9 days - Average sunshine days in October:
20 days - Average sunshine days in November:
19.2 days - Average sunshine days in December:
20.4 days
The month with the most sunshine days is January (20.6 days).
The month with the least sunshine days is July (12.5 days).
Average UV index
Waterloo, IL
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February and December (UV index 2).
Average cloud cover
Waterloo, IL
The month with the most cloud cover is January (Cloud cover 49).
The months with the least cloud cover are June and August (Cloud cover 27).
Average visibility
Waterloo, IL
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
