May weather forecastLetts, IA
May
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).Temperature
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). An average low-temperature of 53.8°F (12.1°C) is recorded during the nights in May.Humidity
In Letts, the average relative humidity in May is 78%.Rainfall
May is the month with the most rainfall. Rain falls for 19.7 days and accumulates 5" (127mm) of precipitation.Snowfall
In Letts, Iowa, snow does not fall in May through September.Daylight
In Letts, the average length of the day in May is 14h and 31min.On the first day of the month, sunrise is at 6:01 am and sunset at 8:02 pm. On the last day of May, sunrise is at 5:34 am and sunset at 8:31 pm CDT.
Sunshine
In Letts, Iowa, the average sunshine in May is 8.9h.UV index
In May, the average daily maximum UV index is 5. A UV Index reading of 3 to 5 represents a medium vulnerability from unsafe exposure to UV radiation for ordinary individuals.Note: A daily maximum UV index of 5 in May translates into the following instructions:
Take measures. Individuals with light skin might experience burns in under 30 minutes. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. Always opt for UVA and UVB-resistant sunglasses on radiant days.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
Letts, IA
- Average high temperature in May: 70.5°F
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).
- Average low temperature in May: 53.8°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 in May
Letts, IA
- Average pressure in May: 29.94"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 in May
Letts, IA
- Average wind speed in May: 8.9mph
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 in May
Letts, IA
- Average humidity in May: 78%
The month with the highest relative humidity is July (83%).
The month with the lowest relative humidity is October (71%).
Average rainfall in May
Letts, IA
- Average rainfall in May: 5"
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 in May
Letts, IA
- Average rainfall days in May: 19.7 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 in May
Letts, IA
- Average snowfall in May: 0"
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 in May
Letts, IA
- Average snowfall days in May: 0 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 in May /
Average sunshine in May
Letts, IA
- Average daylight in May: 14h and 30min
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 May: 8h and 54min
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 in May
Letts, IA
- Average sunshine days in May: 8.5 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 in May
Letts, IA
- Average UV index in May: 5
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 in May
Letts, IA
- Average cloud cover in May: 41
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 in May
Letts, IA
- Average visibility in May: 6mi
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).





