Climate and monthly weather forecastLetts, IA
Climate and monthly weather forecast
Weather in January
January, like December, is another subzero cold winter month in Letts, Iowa, with an average temperature varying between 28.4°F (-2°C) and 16.3°F (-8.7°C). With its high average temperature of 28.4°F (-2°C) and a low of 16.3°F (-8.7°C), January is regarded as the coldest month. Weather in January »Weather in February
February, the last month of the winter in Letts, is an icy month, with an average temperature varying between 33.3°F (0.7°C) and 20.1°F (-6.6°C). Letts transitions into February recording an average high-temperature of an icy 33.3°F (0.7°C), closely aligning with the preceding month's temperature. Weather in February »Weather in March
The first month of the spring, March, is a frosty month in Letts, Iowa, with temperature in the range of an average low of 32.5°F (0.3°C) and an average high of 47.1°F (8.4°C). Letts's transition into March sees a rise in the average high-temperature, advancing from a wintry 33.3°F (0.7°C) in February to a chilly 47.1°F (8.4°C). Weather in March »Weather in April
April is a refreshing spring month in Letts, Iowa, with an average temperature fluctuating between 59.5°F (15.3°C) and 42.6°F (5.9°C). With the onset of April, Letts's average high-temperature experiences a rise, moving from March's frosty 47.1°F (8.4°C) to a mild 59.5°F (15.3°C). Weather in April »Weather in May
May, the last month of the spring in Letts, is an agreeable month, with temperature in the range of an average high of 70.5°F (21.4°C) and an average low of 53.8°F (12.1°C). Letts's transition into May sees a rise in the average high-temperature, advancing from a moderate 59.5°F (15.3°C) in April to a pleasant 70.5°F (21.4°C). Weather in May »Weather in June
The first month of the summer, June, is a moderately hot month in Letts, Iowa, with an average temperature varying between 62.4°F (16.9°C) and 79.3°F (26.3°C). June's arrival sees a mild rise in the average high-temperature, transitioning from May's pleasant 70.5°F (21.4°C) to a warm 79.3°F (26.3°C). Weather in June »Weather in July
July, the same as June, is a moderately hot summer month in Letts, Iowa, with an average temperature fluctuating between 81.7°F (27.6°C) and 64.9°F (18.3°C). With average high temperatures of 81.7°F (27.6°C) and lows of 64.9°F (18.3°C), July is the warmest month. The heat index value during July is estimated at a hot 89.6°F (32°C). Weather in July »Weather in August
August, the last month of the summer in Letts, is also a moderately hot month, with an average temperature fluctuating between 81.1°F (27.3°C) and 63.1°F (17.3°C). Letts, Iowa, registers an average high-temperature of a still warm 81.1°F (27.3°C) with the arrival of August, showing minor deviation from the preceding month. Weather in August »Weather in September
September, the first month of the autumn in Letts, is still a warm month, with temperature in the range of an average low of 56.3°F (13.5°C) and an average high of 75.4°F (24.1°C). September signifies a gentle decline in Letts's average high-temperature, easing from 81.1°F (27.3°C) in August to a still moderately hot 75.4°F (24.1°C). Weather in September »Weather in October
October, like September, in Letts, Iowa, is another enjoyable autumn month, with temperature in the range of an average high of 61.7°F (16.5°C) and an average low of 45.3°F (7.4°C). October is characterized by a reduction in the average high-temperature, from a moderately hot 75.4°F (24.1°C) in September to a comfortable 61.7°F (16.5°C). Weather in October »Weather in November
The last month of the autumn, November, is another chilly month in Letts, Iowa, with temperature in the range of an average high of 47.1°F (8.4°C) and an average low of 33.8°F (1°C). As November sets, the average high-temperature displays a significant decrease, moving down from a refreshing 61.7°F (16.5°C) in October to a frosty 47.1°F (8.4°C). Weather in November »Weather in December
December, the first month of the winter in Letts, is also an icy month, with an average temperature varying between 23.9°F (-4.5°C) and 34.7°F (1.5°C). The average high-temperature decreases in December, shifting from a frosty 47.1°F (8.4°C) in November to a cold 34.7°F (1.5°C). Weather in December »Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature
Letts, IA
The warmest month (with the highest average high temperature) is July (81.7°F).
The month with the lowest average high temperature is January (28.4°F).
The month with the highest average low temperature is July (64.9°F).
The coldest month (with the lowest average low temperature) is January (16.3°F).
Average pressure
Letts, IA
- Average pressure in January:
30.14"Hg - Average pressure in February:
30.12"Hg - Average pressure in March:
30.07"Hg - Average pressure in April:
29.93"Hg - Average pressure in May:
29.94"Hg - Average pressure in June:
29.9"Hg
- Average pressure in July:
29.96"Hg - Average pressure in August:
29.97"Hg - Average pressure in September:
30.02"Hg - Average pressure in October:
30.01"Hg - Average pressure in November:
30.09"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 (29.9"Hg).
Average wind speed
Letts, IA
- Average wind speed in January:
10.4mph - Average wind speed in February:
10.4mph - Average wind speed in March:
10.4mph - Average wind speed in April:
10.6mph - Average wind speed in May:
8.9mph - Average wind speed in June:
7.8mph
- Average wind speed in July:
6.8mph - Average wind speed in August:
6.8mph - Average wind speed in September:
7.8mph - Average wind speed in October:
9.5mph - Average wind speed in November:
10.3mph - Average wind speed in December:
9.8mph
The windiest month (with the highest average wind speed) is April (10.6mph).
The calmest months (with the lowest average wind speed) are July and August (6.8mph).
Average humidity
Letts, IA
The month with the highest relative humidity is July (83%).
The month with the lowest relative humidity is October (71%).
Average rainfall
Letts, IA
- Average rainfall in January:
1.5" - Average rainfall in February:
1.46" - Average rainfall in March:
2.17" - Average rainfall in April:
3.39" - Average rainfall in May:
5" - Average rainfall in June:
4.33"
The wettest month (with the highest rainfall) is May (5").
The driest months (with the least rainfall) are February and December (1.46").
Average rainfall days
Letts, IA
- Average rainfall days in January:
6.3 days - Average rainfall days in February:
6.3 days - Average rainfall days in March:
13.8 days - Average rainfall days in April:
16.8 days - Average rainfall days in May:
19.7 days - Average rainfall days in June:
18.9 days
- Average rainfall days in July:
16.6 days - Average rainfall days in August:
14.2 days - Average rainfall days in September:
12.3 days - Average rainfall days in October:
11.8 days - Average rainfall days in November:
9.3 days - Average rainfall days in December:
7.8 days
The month with the highest number of rainy days is May (19.7 days).
The months with the least rainy days are January and February (6.3 days).
Average snowfall
Letts, IA
The month with the highest snowfall is January (4.92").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days
Letts, IA
- Average snowfall days in January:
12.2 days - Average snowfall days in February:
10.1 days - Average snowfall days in March:
5.5 days - Average snowfall days in April:
1.2 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:
0.4 days - Average snowfall days in November:
2.7 days - Average snowfall days in December:
8 days
The month with the highest number of snowfall days is January (12.2 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight / Average sunshine
Letts, IA
- 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 30min - Average daylight in June:
15h and 6min
- Average daylight in July:
14h and 48min - 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 54min - Average daylight in December:
9h and 18min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in January:
4h and 12min - Average sunshine in February:
4h and 18min - Average sunshine in March:
6h and 36min - Average sunshine in April:
8h and 0min - Average sunshine in May:
8h and 54min - Average sunshine in June:
10h and 0min
- Average sunshine in July:
10h and 12min - Average sunshine in August:
10h and 0min - Average sunshine in September:
9h and 24min - Average sunshine in October:
5h and 30min - Average sunshine in November:
5h and 24min - Average sunshine in December:
4h and 36min
The month with the most sunshine is July (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 4h and 12min).
Average sunshine days
Letts, IA
- Average sunshine days in January:
15.3 days - Average sunshine days in February:
13.7 days - Average sunshine days in March:
13.2 days - Average sunshine days in April:
10.8 days - Average sunshine days in May:
8.5 days - Average sunshine days in June:
8.3 days
- Average sunshine days in July:
9.8 days - Average sunshine days in August:
13.3 days - Average sunshine days in September:
15.6 days - Average sunshine days in October:
16.6 days - Average sunshine days in November:
17.2 days - Average sunshine days in December:
16.8 days
The month with the most sunshine days is November (17.2 days).
The month with the least sunshine days is June (8.3 days).
Average UV index
Letts, IA
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover
Letts, IA
The month with the most cloud cover is January (Cloud cover 55).
The months with the least cloud cover are August and September (Cloud cover 29).
Average visibility
Letts, IA
The months with the highest visibility are January, February, March, April, May, June, August, September, October, November and December (6mi).
The month with the lowest visibility is July (5mi).





