Climate and monthly weather forecastRock Valley, IA
Climate and monthly weather forecast
Weather in January
January, like December, is another subzero cold winter month in Rock Valley, Iowa, with an average temperature fluctuating between 10.8°F (-11.8°C) and 24.1°F (-4.4°C). January, recording an average high temperature of 24.1°F (-4.4°C) and a low temperature of 10.8°F (-11.8°C), is Rock Valley's coldest month. Weather in January »Weather in February
February, the last month of the winter in Rock Valley, is another freezing cold month, with an average temperature ranging between min 14.4°F (-9.8°C) and max 27.7°F (-2.4°C). With the advent of February, Rock Valley's high-temperatures adjust to a still subzero cold 27.7°F (-2.4°C), closely aligning with the preceding month. Weather in February »Weather in March
March, the first month of the spring in Rock Valley, is a chilly month, with an average temperature ranging between max 44.1°F (6.7°C) and min 28.9°F (-1.7°C). March's arrival witnesses a distinct temperature rise, advancing from February's subzero cold 27.7°F (-2.4°C) to a frosty 44.1°F (6.7°C). Weather in March »Weather in April
April is a refreshing spring month in Rock Valley, Iowa, with an average temperature fluctuating between 56.3°F (13.5°C) and 39.9°F (4.4°C). As April arrives, a rise in the average high-temperature is observed, moving from a chilly 44.1°F (6.7°C) in March to a moderate 56.3°F (13.5°C). Weather in April »Weather in May
The last month of the spring, May, is an agreeable month in Rock Valley, Iowa, with an average temperature ranging between min 51.1°F (10.6°C) and max 68.5°F (20.3°C). May brings a rise in Rock Valley's average high-temperature, moving from a refreshing 56.3°F (13.5°C) in April to an agreeable 68.5°F (20.3°C). Weather in May »Weather in June
June, the first month of the summer in Rock Valley, is a warm month, with an average temperature ranging between min 61.3°F (16.3°C) and max 77.9°F (25.5°C). The transition from May to June brings a temperature rise, with average high-temperatures increasing from an agreeable 68.5°F (20.3°C) to a warm 77.9°F (25.5°C). Weather in June »Weather in July
July, like June, in Rock Valley, Iowa, is another warm summer month, with temperature in the range of an average high of 81.9°F (27.7°C) and an average low of 63.5°F (17.5°C). July, with an average high of 81.9°F (27.7°C) and a low of 63.5°F (17.5°C), signifies the warmest month of the year. During July, the heat index is evaluated at a hot 87.8°F (31°C). Weather in July »Weather in August
August, the last month of the summer in Rock Valley, is another warm month, with an average temperature ranging between min 60.3°F (15.7°C) and max 80.4°F (26.9°C). The transition from July to August brings an average high-temperature of a still moderately hot 80.4°F (26.9°C), barely different from July's 81.9°F (27.7°C). Weather in August »Weather in September
The first month of the autumn, September, is still a warm month in Rock Valley, Iowa, with temperature in the range of an average low of 54°F (12.2°C) and an average high of 74.3°F (23.5°C). September witnesses a gentle descent in average high-temperature, descending from August's 80.4°F (26.9°C) to a still moderately hot 74.3°F (23.5°C). Weather in September »Weather in October
October, the same as September, in Rock Valley, Iowa, is a moderate autumn month, with temperature in the range of an average high of 58.1°F (14.5°C) and an average low of 41.9°F (5.5°C). Witnessing a clear downswing, the average high-temperature during October drops from September's warm 74.3°F (23.5°C) to a moderate 58.1°F (14.5°C). Weather in October »Weather in November
The last month of the autumn, November, is also a frosty month in Rock Valley, Iowa, with an average temperature varying between 43.7°F (6.5°C) and 30°F (-1.1°C). As October gives way to November, the average high-temperature displays a considerable decrease, falling from a mild 58.1°F (14.5°C) to a chilly 43.7°F (6.5°C). Weather in November »Weather in December
December, the first month of the winter in Rock Valley, is also a subzero cold month, with an average temperature fluctuating between 16.7°F (-8.5°C) and 28°F (-2.2°C). Rock Valley in December showcases a distinct temperature shift, moving from an average high of a frosty 43.7°F (6.5°C) in November to a freezing cold 28°F (-2.2°C). Weather in December »Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature
Rock Valley, IA
The warmest month (with the highest average high temperature) is July (81.9°F).
The month with the lowest average high temperature is January (24.1°F).
The month with the highest average low temperature is July (63.5°F).
The coldest month (with the lowest average low temperature) is January (10.8°F).
Average pressure
Rock Valley, IA
- Average pressure in January:
30.16"Hg - Average pressure in February:
30.15"Hg - Average pressure in March:
30.06"Hg - Average pressure in April:
29.93"Hg - Average pressure in May:
29.92"Hg - Average pressure in June:
29.86"Hg
- Average pressure in July:
29.94"Hg - Average pressure in August:
29.94"Hg - Average pressure in September:
29.98"Hg - Average pressure in October:
29.99"Hg - Average pressure in November:
30.07"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 (29.86"Hg).
Average wind speed
Rock Valley, IA
- Average wind speed in January:
10.4mph - Average wind speed in February:
10.4mph - Average wind speed in March:
10.7mph - Average wind speed in April:
11.2mph - Average wind speed in May:
9.6mph - Average wind speed in June:
8.8mph
- Average wind speed in July:
7.8mph - Average wind speed in August:
8mph - Average wind speed in September:
9.2mph - Average wind speed in October:
10.3mph - Average wind speed in November:
10.3mph - Average wind speed in December:
10mph
The windiest month (with the highest average wind speed) is April (11.2mph).
The calmest month (with the lowest average wind speed) is July (7.8mph).
Average humidity
Rock Valley, IA
The month with the highest relative humidity is January (87%).
The month with the lowest relative humidity is October (67%).
Average rainfall
Rock Valley, IA
- Average rainfall in January:
0.75" - Average rainfall in February:
0.87" - Average rainfall in March:
1.65" - Average rainfall in April:
2.72" - Average rainfall in May:
3.35" - Average rainfall in June:
3.78"
The wettest month (with the highest rainfall) is June (3.78").
The driest month (with the least rainfall) is January (0.75").
Average rainfall days
Rock Valley, IA
- Average rainfall days in January:
4.2 days - Average rainfall days in February:
3.3 days - Average rainfall days in March:
10.3 days - Average rainfall days in April:
13.8 days - Average rainfall days in May:
17.9 days - Average rainfall days in June:
18.8 days
- Average rainfall days in July:
14.6 days - Average rainfall days in August:
13.8 days - Average rainfall days in September:
11.8 days - Average rainfall days in October:
10.5 days - Average rainfall days in November:
6.1 days - Average rainfall days in December:
4.9 days
The month with the highest number of rainy days is June (18.8 days).
The month with the least rainy days is February (3.3 days).
Average snowfall
Rock Valley, IA
- Average snowfall in January:
3.23" - Average snowfall in February:
4.49" - Average snowfall in March:
3.07" - Average snowfall in April:
2.64" - Average snowfall in May:
0.24" - Average snowfall in June:
0"
The month with the highest snowfall is February (4.49").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days
Rock Valley, IA
- Average snowfall days in January:
11.8 days - Average snowfall days in February:
9.7 days - Average snowfall days in March:
7.9 days - Average snowfall days in April:
2.7 days - Average snowfall days in May:
0.3 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:
1.5 days - Average snowfall days in November:
4.3 days - Average snowfall days in December:
11 days
The month with the highest number of snowfall days is January (11.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
Rock Valley, IA
- Average daylight in January:
9h and 24min - Average daylight in February:
10h and 30min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 24min - Average daylight in May:
14h and 42min - Average daylight in June:
15h and 18min
- Average daylight in July:
15h and 0min - Average daylight in August:
13h and 54min - Average daylight in September:
12h and 30min - Average daylight in October:
11h and 0min - Average daylight in November:
9h and 42min - Average daylight in December:
9h and 0min
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 0min).
- Average sunshine in January:
4h and 6min - Average sunshine in February:
5h and 6min - Average sunshine in March:
6h and 18min - Average sunshine in April:
8h and 6min - Average sunshine in May:
8h and 48min - Average sunshine in June:
10h and 0min
- Average sunshine in July:
10h and 36min - Average sunshine in August:
9h and 54min - Average sunshine in September:
8h and 54min - Average sunshine in October:
6h and 6min - Average sunshine in November:
5h and 42min - Average sunshine in December:
4h and 30min
The month with the most sunshine is July (Average sunshine: 10h and 36min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days
Rock Valley, IA
- Average sunshine days in January:
17.2 days - Average sunshine days in February:
15.2 days - Average sunshine days in March:
13.8 days - Average sunshine days in April:
12.4 days - Average sunshine days in May:
11.2 days - Average sunshine days in June:
8.3 days
- Average sunshine days in July:
12.8 days - Average sunshine days in August:
13.1 days - Average sunshine days in September:
15.3 days - Average sunshine days in October:
17.9 days - Average sunshine days in November:
19.7 days - Average sunshine days in December:
18 days
The month with the most sunshine days is November (19.7 days).
The month with the least sunshine days is June (8.3 days).
Average UV index
Rock Valley, IA
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January, February, October, November and December (UV index 2).
Average cloud cover
Rock Valley, IA
The month with the most cloud cover is January (Cloud cover 55).
The month with the least cloud cover is July (Cloud cover 27).
Average visibility
Rock Valley, IA
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).





