Climate and monthly weather forecastGrafton, IA
Climate and monthly weather forecast
Weather in January
January, the same as December, in Grafton, Iowa, is another subzero cold winter month, with temperature in the range of an average high of 21.6°F (-5.8°C) and an average low of 9°F (-12.8°C). January proves to be the coldest month, recording an average maximum temperature of 21.6°F (-5.8°C) and a minimum temperature of 9°F (-12.8°C). Weather in January »Weather in February
The last month of the winter, February, is another freezing cold month in Grafton, Iowa, with temperature in the range of an average high of 25.3°F (-3.7°C) and an average low of 12.4°F (-10.9°C). As Grafton transitions into February, the average high-temperature stands at a still subzero cold 25.3°F (-3.7°C), offering little variation from the preceding month. Weather in February »Weather in March
March, the first month of the spring in Grafton, is an icy month, with temperature in the range of an average low of 27°F (-2.8°C) and an average high of 40.6°F (4.8°C). March marks a distinct rise in the average high-temperature, ascending from February's freezing cold 25.3°F (-3.7°C) to a cold 40.6°F (4.8°C). Weather in March »Weather in April
April in Grafton, Iowa, is a cool spring month, with an average temperature varying between 38.7°F (3.7°C) and 54.3°F (12.4°C). With the onset of April, Grafton's weather sees a temperature rise, transitioning from a cold 40.6°F (4.8°C) in March to a cool 54.3°F (12.4°C). Weather in April »Weather in May
The last month of the spring, May, is an enjoyable month in Grafton, Iowa, with an average temperature ranging between max 66.6°F (19.2°C) and min 50.4°F (10.2°C). With the onset of May, Grafton's average high-temperature sees a rise, moving from April's cool 54.3°F (12.4°C) to a comfortable 66.6°F (19.2°C). Weather in May »Weather in June
June, the first month of the summer in Grafton, is a warm month, with an average temperature ranging between max 76.5°F (24.7°C) and min 60.3°F (15.7°C). In Grafton, stepping into June brings a temperature increase, moving up from May's enjoyable 66.6°F (19.2°C) to a moderately hot 76.5°F (24.7°C). Weather in June »Weather in July
July, like June, in Grafton, Iowa, is a moderately hot summer month, with an average temperature varying between 62.6°F (17°C) and 79.2°F (26.2°C). July, with its average high-temperature of 79.2°F (26.2°C) and an average low-temperature of 62.6°F (17°C), holds the record as the warmest month. Weather in July »Weather in August
The last month of the summer, August, is also a moderately hot month in Grafton, Iowa, with an average temperature ranging between min 59.5°F (15.3°C) and max 76.8°F (24.9°C). Grafton records an average high-temperature of a still moderately hot 76.8°F (24.9°C) as August arrives, nearly mirroring the previous month's climate. Weather in August »Weather in September
September, the first month of the autumn in Grafton, is also an agreeable month, with temperature in the range of an average high of 71.4°F (21.9°C) and an average low of 53.1°F (11.7°C). Grafton's weather subtly changes with the onset of September, barely falling from a moderately hot 76.8°F (24.9°C) in August to a pleasant 71.4°F (21.9°C). Weather in September »Weather in October
October, like September, is another mild autumn month in Grafton, Iowa, with temperature in the range of an average high of 56.3°F (13.5°C) and an average low of 41.7°F (5.4°C). The shift into October is marked by a noticeable reduction in the average high-temperature, decreasing from September's agreeable 71.4°F (21.9°C) to a refreshing 56.3°F (13.5°C). Weather in October »Weather in November
The last month of the autumn, November, is another cold month in Grafton, Iowa, with an average temperature fluctuating between 41.4°F (5.2°C) and 29.5°F (-1.4°C). The start of November signals a clear decrease in the average high-temperature, falling from a refreshing 56.3°F (13.5°C) in October to a wintry 41.4°F (5.2°C). Weather in November »Weather in December
The first month of the winter, December, is still a freezing cold month in Grafton, Iowa, with temperature in the range of an average low of 16.5°F (-8.6°C) and an average high of 27.3°F (-2.6°C). The arrival of December corresponds with a temperature reduction, down from November's icy 41.4°F (5.2°C) to a freezing cold 27.3°F (-2.6°C). Weather in December »Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature
Grafton, 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 (21.6°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 (9°F).
Average pressure
Grafton, IA
- Average pressure in January:
30.14"Hg - Average pressure in February:
30.14"Hg - Average pressure in March:
30.08"Hg - Average pressure in April:
29.94"Hg - Average pressure in May:
29.93"Hg - Average pressure in June:
29.88"Hg
- Average pressure in July:
29.96"Hg - Average pressure in August:
29.96"Hg - Average pressure in September:
30.01"Hg - Average pressure in October:
29.99"Hg - Average pressure in November:
30.07"Hg - Average pressure in December:
30.11"Hg
The months with the highest atmospheric pressure are January and February (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed
Grafton, IA
- Average wind speed in January:
10.7mph - Average wind speed in February:
10.6mph - Average wind speed in March:
10.5mph - Average wind speed in April:
10.8mph - Average wind speed in May:
9.4mph - Average wind speed in June:
8.5mph
- Average wind speed in July:
7.4mph - Average wind speed in August:
7.4mph - Average wind speed in September:
8.6mph - Average wind speed in October:
10mph - Average wind speed in November:
10.6mph - 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 (7.4mph).
Average humidity
Grafton, IA
The month with the highest relative humidity is January (90%).
The months with the lowest relative humidity are April and October (72%).
Average rainfall
Grafton, IA
- Average rainfall in January:
0.94" - Average rainfall in February:
1.18" - Average rainfall in March:
1.38" - Average rainfall in April:
2.6" - Average rainfall in May:
3.07" - Average rainfall in June:
4.13"
The wettest month (with the highest rainfall) is June (4.13").
The driest month (with the least rainfall) is January (0.94").
Average rainfall days
Grafton, IA
- Average rainfall days in January:
4.5 days - Average rainfall days in February:
2.9 days - Average rainfall days in March:
10.1 days - Average rainfall days in April:
14.9 days - Average rainfall days in May:
17.2 days - Average rainfall days in June:
18.4 days
- Average rainfall days in July:
16.3 days - Average rainfall days in August:
14.7 days - Average rainfall days in September:
11.8 days - Average rainfall days in October:
10.5 days - Average rainfall days in November:
7.5 days - Average rainfall days in December:
5.5 days
The month with the highest number of rainy days is June (18.4 days).
The month with the least rainy days is February (2.9 days).
Average snowfall
Grafton, IA
- Average snowfall in January:
4.84" - Average snowfall in February:
5.94" - Average snowfall in March:
3.11" - Average snowfall in April:
2.48" - Average snowfall in May:
0.47" - Average snowfall in June:
0"
The month with the highest snowfall is February (5.94").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days
Grafton, IA
- Average snowfall days in January:
13.8 days - Average snowfall days in February:
12.2 days - Average snowfall days in March:
7.9 days - Average snowfall days in April:
3.3 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:
1.4 days - Average snowfall days in November:
5.5 days - Average snowfall days in December:
12.6 days
The month with the highest number of snowfall days is January (13.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
Grafton, 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:
3h and 24min - Average sunshine in February:
3h and 42min - Average sunshine in March:
5h and 36min - Average sunshine in April:
7h and 30min - Average sunshine in May:
8h and 24min - Average sunshine in June:
9h and 18min
- Average sunshine in July:
9h and 48min - Average sunshine in August:
9h and 36min - Average sunshine in September:
8h and 54min - Average sunshine in October:
5h and 24min - Average sunshine in November:
5h and 6min - Average sunshine in December:
3h and 54min
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 24min).
Average sunshine days
Grafton, IA
- Average sunshine days in January:
14.1 days - Average sunshine days in February:
13.8 days - Average sunshine days in March:
14.3 days - Average sunshine days in April:
11.9 days - Average sunshine days in May:
11.7 days - Average sunshine days in June:
9.1 days
- Average sunshine days in July:
11.4 days - Average sunshine days in August:
14 days - Average sunshine days in September:
15.1 days - Average sunshine days in October:
18.1 days - Average sunshine days in November:
17.5 days - Average sunshine days in December:
14.7 days
The month with the most sunshine days is October (18.1 days).
The month with the least sunshine days is June (9.1 days).
Average UV index
Grafton, 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, November and December (UV index 1).
Average cloud cover
Grafton, IA
The month with the most cloud cover is January (Cloud cover 65).
The month with the least cloud cover is August (Cloud cover 32).
Average visibility
Grafton, IA
The months with the highest visibility are March, April, May, June, September, October and November (6mi).
The months with the lowest visibility are January, February, July, August and December (5mi).





