May weather forecastSumner, IA
May
Weather in May
May, the last month of the spring in Sumner, is a refreshing month, with an average temperature fluctuating between 50.5°F (10.3°C) and 66.7°F (19.3°C).Temperature
May indicates a change in the average high-temperature, moving up from a fresh 55°F (12.8°C) in April to a refreshing 66.7°F (19.3°C). In Sumner, the expected average low-temperature for May is a cool 50.5°F (10.3°C).Humidity
In May, the average relative humidity is 78%.Rainfall
In Sumner, in May, it is raining for 20.3 days, with typically 4.45" (113mm) of accumulated precipitation. Throughout the year, there are 146.8 rainfall days, and 30.79" (782mm) of precipitation is accumulated.Snowfall
January through May, October through December are months with snowfall. May is the last month it regularly snows. During 0.2 snowfall days, in May, Sumner aggregates 0.24" (6mm) of snow. In Sumner, during the entire year, snow falls for 55.9 days and aggregates up to 23.46" (596mm) of snow.Daylight
The average length of the day in May is 14h and 40min.On the first day of the month, sunrise is at 6:01 am and sunset at 8:09 pm. On the last day of May, sunrise is at 5:32 am and sunset at 8:39 pm CDT.
Sunshine
In Sumner, the average sunshine in May is 8.4h.UV index
In Sumner, the average daily maximum UV index in May is 5. A UV Index value of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV rays for ordinary individuals.Note: A daily maximum UV index of 5 in May translates into the following instructions:
Heed the precautions - Protecting the skin and eyes from damage is compulsory. Midday Sun has the strongest UV rays, making it crucial to limit exposure and find shade. Safeguard your eyes, ears, and face from sun rays with the aid of a wide-brim hat. Stay alert! Snow's reflective properties can almost double the UV radiation from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
Sumner, IA
- Average high temperature in May: 66.7°F
The warmest month (with the highest average high temperature) is July (79.2°F).
The month with the lowest average high temperature is January (23.5°F).
- Average low temperature in May: 50.5°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 (11.1°F).
Average pressure in May
Sumner, 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 (29.89"Hg).
Average wind speed in May
Sumner, IA
- Average wind speed in May: 9.3mph
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 (7.1mph).
Average humidity in May
Sumner, IA
- Average humidity in May: 78%
The months with the highest relative humidity are January and February (88%).
The month with the lowest relative humidity is October (73%).
Average rainfall in May
Sumner, IA
- Average rainfall in May: 4.45"
The wettest month (with the highest rainfall) is June (5.04").
The driest month (with the least rainfall) is January (1.14").
Average rainfall days in May
Sumner, IA
- Average rainfall days in May: 20.3 days
The month with the highest number of rainy days is May (20.3 days).
The months with the least rainy days are January and February (4.3 days).
Average snowfall in May
Sumner, IA
- Average snowfall in May: 0.24"
The month with the highest snowfall is February (5.83").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in May
Sumner, IA
- Average snowfall days in May: 0.2 days
The month with the highest number of snowfall days is January (13.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in May /
Average sunshine in May
Sumner, IA
- Average daylight in May: 14h and 42min
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 6min).
- Average sunshine in May: 8h and 24min
The months with the most sunshine are July and August (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 36min).
Average sunshine days in May
Sumner, IA
- Average sunshine days in May: 8.9 days
The month with the most sunshine days is November (16.8 days).
The month with the least sunshine days is June (7.3 days).
Average UV index in May
Sumner, IA
- Average UV index in May: 5
The month with the highest UV index is June (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in May
Sumner, IA
- Average cloud cover in May: 43
The month with the most cloud cover is January (Cloud cover 62).
The months with the least cloud cover are August and September (Cloud cover 32).
Average visibility in May
Sumner, IA
- Average visibility in May: 6mi
The months with the highest visibility are March, April, May, June, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February and July (5mi).





