Climate and monthly weather forecastRock Falls, IL
Climate and monthly weather forecast
Weather in January
January, like December, is a freezing cold winter month in Rock Falls, Illinois, with an average temperature varying between 14.9°F (-9.5°C) and 27.7°F (-2.4°C). January is the coldest month of the year, registering average temperatures as high as 27.7°F (-2.4°C) and as low as 14.9°F (-9.5°C). Weather in January »Weather in February
February, the last month of the winter in Rock Falls, is another freezing cold month, with an average temperature varying between 18.5°F (-7.5°C) and 31.6°F (-0.2°C). Rock Falls sees the arrival of February with an average high-temperature of a still freezing cold 31.6°F (-0.2°C), indicating a subtle variation from January. Weather in February »Weather in March
The first month of the spring, March, is a frosty month in Rock Falls, Illinois, with an average temperature ranging between min 31.3°F (-0.4°C) and max 45.9°F (7.7°C). Rock Falls in March sees a temperature change, with average high-temperatures moving from a freezing cold 31.6°F (-0.2°C) in February to a chilly 45.9°F (7.7°C). Weather in March »Weather in April
April is a mild spring month in Rock Falls, Illinois, with an average temperature ranging between max 57.9°F (14.4°C) and min 41.4°F (5.2°C). April brings a rise in the average high-temperature, transitioning from March's chilly 45.9°F (7.7°C) to a moderate 57.9°F (14.4°C). Weather in April »Weather in May
May, the last month of the spring in Rock Falls, is an agreeable month, with an average temperature fluctuating between 69.4°F (20.8°C) and 52.5°F (11.4°C). With the onset of May, Rock Falls's weather sees a temperature rise, transitioning from a moderate 57.9°F (14.4°C) in April to a pleasant 69.4°F (20.8°C). Weather in May »Weather in June
June, the first month of the summer in Rock Falls, is a moderately hot month, with an average temperature ranging between max 78.3°F (25.7°C) and min 61.3°F (16.3°C). The onset of June marks a slight increase in the average high-temperature, moving from a pleasant 69.4°F (20.8°C) in May to a warm 78.3°F (25.7°C). Weather in June »Weather in July
July, the same as June, is another warm summer month in Rock Falls, Illinois, with an average temperature fluctuating between 80.2°F (26.8°C) and 63.9°F (17.7°C). Rock Falls, Illinois, experiences its highest average temperatures in July, reaching a peak of 80.2°F (26.8°C) and a minimum of 63.9°F (17.7°C). Weather in July »Weather in August
August, the last month of the summer in Rock Falls, is also a moderately hot month, with an average temperature fluctuating between 79.3°F (26.3°C) and 61.7°F (16.5°C). August brings an average high-temperature of a still moderately hot 79.3°F (26.3°C), nearly identical to the preceding month. Weather in August »Weather in September
September, the first month of the autumn in Rock Falls, is still a warm month, with temperature in the range of an average high of 73.9°F (23.3°C) and an average low of 55.2°F (12.9°C). In September, the meteorological conditions change slightly, with the average high-temperature moving from 79.3°F (26.3°C) in August to a still moderately hot 73.9°F (23.3°C). Weather in September »Weather in October
October, the same as September, in Rock Falls, Illinois, is a moderate autumn month, with an average temperature ranging between max 60.6°F (15.9°C) and min 44.6°F (7°C). In October, the average high-temperature goes from a warm 73.9°F (23.3°C) in September to a mild 60.6°F (15.9°C). Weather in October »Weather in November
November, the last month of the autumn in Rock Falls, is also a frosty month, with an average temperature ranging between min 32.4°F (0.2°C) and max 45.5°F (7.5°C). November's arrival signals a distinct temperature shift, dropping from a moderate 60.6°F (15.9°C) in October to a chilly 45.5°F (7.5°C). Weather in November »Weather in December
December, the first month of the winter in Rock Falls, is still a cold month, with an average temperature fluctuating between 23.2°F (-4.9°C) and 33.8°F (1°C). The commencement of December involves a temperature shift, with the average high-temperature dropping from a frosty 45.5°F (7.5°C) in November to a cold 33.8°F (1°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
Rock Falls experiences its average lowest temperatures in January, reaching a peak of 27.7°F (-2.4°C) and a minimum of 14.9°F (-9.5°C).
January and July, with an average relative humidity of 85%, are most humid months.
The months with the least rainfall are January and February Rain falls for 4.8 days and accumulates 0.75" (19mm) of rain.
In Rock Falls, during the entire year, the rain falls for 130.2 days and collects up to 17.36" (441mm) of precipitation.
January through April, October through December are months with snowfall.
January is the month with the most snowfall. Snow falls for 10.2 days and accumulates 2.56" (65mm) of snow.
Throughout the year, in Rock Falls, there are 34.2 snowfall days, and 7.87" (200mm) of snow is accumulated.
With an average of 3.8h of sunshine, January has the least sunshine of the year.
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.
The month with the most rainfall is May, when the rain falls for 17.3 days and typically aggregates up to 2.83" (72mm) of precipitation.
May through September are months without snowfall.
June has the longest days of the year, with an average of 15h and 12min of daylight.
The warmest time of the year is July, with temperatures averaging a high of 80.2°F (26.8°C) and a low of 63.9°F (17.7°C).
The month with the most sunshine is July, with an average of 9.8h of sunshine.
With an average maximum UV index of 6, July is the month with the highest UV index.
The least humid month is October, with an average relative humidity of 73%.
With an average of 9h and 12min of daylight, December has the shortest days of the year.
With an average maximum UV index of 1, December is the month with the lowest UV index.
Average temperature
Rock Falls, IL
The warmest month (with the highest average high temperature) is July (80.2°F).
The month with the lowest average high temperature is January (27.7°F).
The month with the highest average low temperature is July (63.9°F).
The coldest month (with the lowest average low temperature) is January (14.9°F).
Average pressure
Rock Falls, IL
- Average pressure in January:
30.12"Hg - Average pressure in February:
30.11"Hg - Average pressure in March:
30.08"Hg - Average pressure in April:
29.94"Hg - Average pressure in May:
29.95"Hg - Average pressure in June:
29.91"Hg
- Average pressure in July:
29.96"Hg - Average pressure in August:
29.97"Hg - Average pressure in September:
30.03"Hg - Average pressure in October:
30.01"Hg - Average pressure in November:
30.09"Hg - Average pressure in December:
30.1"Hg
The month with the highest atmospheric pressure is January (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed
Rock Falls, 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:
10.4mph - Average wind speed in May:
8.8mph - Average wind speed in June:
7.6mph
- Average wind speed in July:
6.5mph - Average wind speed in August:
6.4mph - Average wind speed in September:
7.6mph - Average wind speed in October:
9.1mph - Average wind speed in November:
9.9mph - Average wind speed in December:
9.5mph
The windiest month (with the highest average wind speed) is April (10.4mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity
Rock Falls, IL
The months with the highest relative humidity are January and July (85%).
The month with the lowest relative humidity is October (73%).
Average rainfall
Rock Falls, IL
- Average rainfall in January:
0.75" - Average rainfall in February:
0.75" - Average rainfall in March:
1.1" - Average rainfall in April:
1.89" - Average rainfall in May:
2.83" - Average rainfall in June:
2.13"
- Average rainfall in July:
1.81" - Average rainfall in August:
1.34" - Average rainfall in September:
1.26" - Average rainfall in October:
1.65" - Average rainfall in November:
1.02" - Average rainfall in December:
0.83"
The wettest month (with the highest rainfall) is May (2.83").
The driest months (with the least rainfall) are January and February (0.75").
Average rainfall days
Rock Falls, IL
- Average rainfall days in January:
4.8 days - Average rainfall days in February:
5 days - Average rainfall days in March:
11.1 days - Average rainfall days in April:
14.8 days - Average rainfall days in May:
17.3 days - Average rainfall days in June:
16.5 days
- Average rainfall days in July:
14.1 days - Average rainfall days in August:
12.5 days - Average rainfall days in September:
9.7 days - Average rainfall days in October:
10.8 days - Average rainfall days in November:
7.9 days - Average rainfall days in December:
5.7 days
The month with the highest number of rainy days is May (17.3 days).
The month with the least rainy days is January (4.8 days).
Average snowfall
Rock Falls, IL
The month with the highest snowfall is January (2.56").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days
Rock Falls, IL
- Average snowfall days in January:
10.2 days - Average snowfall days in February:
8.2 days - Average snowfall days in March:
4.4 days - Average snowfall days in April:
1 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:
0.5 days - Average snowfall days in November:
2.5 days - Average snowfall days in December:
7.4 days
The month with the highest number of snowfall days is January (10.2 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight / Average sunshine
Rock Falls, IL
- Average daylight in January:
9h and 36min - Average daylight in February:
10h and 36min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 24min - Average daylight in May:
14h and 36min - Average daylight in June:
15h and 12min
- Average daylight in July:
14h and 54min - Average daylight in August:
13h and 48min - Average daylight in September:
12h and 30min - Average daylight in October:
11h and 6min - Average daylight in November:
9h and 48min - Average daylight in December:
9h and 12min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in January:
3h and 48min - Average sunshine in February:
4h and 0min - Average sunshine in March:
6h and 24min - Average sunshine in April:
7h and 42min - Average sunshine in May:
8h and 36min - Average sunshine in June:
9h and 42min
- Average sunshine in July:
9h and 48min - Average sunshine in August:
9h and 42min - Average sunshine in September:
9h and 6min - Average sunshine in October:
5h and 30min - Average sunshine in November:
5h and 12min - Average sunshine in December:
4h and 6min
The month with the most sunshine is July (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days
Rock Falls, IL
- Average sunshine days in January:
17 days - Average sunshine days in February:
16.2 days - Average sunshine days in March:
16.7 days - Average sunshine days in April:
13.1 days - Average sunshine days in May:
11.4 days - Average sunshine days in June:
11.3 days
- Average sunshine days in July:
12.7 days - Average sunshine days in August:
15.8 days - Average sunshine days in September:
18.4 days - Average sunshine days in October:
18.6 days - Average sunshine days in November:
18.8 days - Average sunshine days in December:
18.8 days
The months with the most sunshine days are November and December (18.8 days).
The month with the least sunshine days is June (11.3 days).
Average UV index
Rock Falls, IL
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover
Rock Falls, IL
The month with the most cloud cover is January (Cloud cover 60).
The month with the least cloud cover is September (Cloud cover 31).
Average visibility
Rock Falls, 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).
