Contents
- Weather in May
- Frequently asked questions
- Average temperature in May
- Average pressure in May
- Average wind speed in May
- Average humidity in May
- Average rainfall in May
- Average rainfall days in May
- Average snowfall in May
- Average snowfall days in May
- Average daylight in May
- Average sunshine in May
- Average sunshine days in May
- Average UV index in May
- Average cloud cover in May
- Average visibility in May
Weather in May
Temperature
Duncan sees an increase in average high-temperatures during May, moving from a mild 55.8°F (13.2°C) in April to a pleasant 68°F (20°C). In Duncan, the May nights cool down to an average low of 51.8°F (11°C).Humidity
The average relative humidity in May is 72%.Rainfall
In Duncan, in May, it is raining for 16 days, with typically 3.15" (80mm) of accumulated precipitation. In Duncan, during the entire year, the rain falls for 127.1 days and collects up to 24.8" (630mm) of precipitation.Snowfall
Months with snowfall in Duncan, Iowa, are January through May, October through December. May is the last month it regularly snows. During 0.3 snowfall days, in May, Duncan aggregates 0.35" (9mm) of snow. Throughout the year, there are 51.2 snowfall days, and 20.91" (531mm) of snow is accumulated.Daylight
The average length of the day in May is 14h and 41min.On the first day of the month, sunrise is at 6:07 am and sunset at 8:16 pm. On the last day of May, sunrise is at 5:38 am and sunset at 8:47 pm CDT.
Sunshine
In Duncan, the average sunshine in May is 8.6h.UV index
In Duncan, the average daily maximum UV index in May is 5. A UV Index of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV radiation for average individuals.Note: A maximum daily UV index of 5 during May morphs into the following directions:
Adopt protective measures - Requirement to safeguard skin and eyes from harm exists. The solar radiation around mid-day is intense; avoid the Sun and stay safe. Counter UV radiation's ill effects with clothing designed for sun safety and UV-resistant eyewear. 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
What is the temperature in May?
What is the average humidity in May?
How much does it rain in May?
What is the last month it snows?
What is the average length of the day in May?
When are sunrise and sunset in May?
How many hours of sunshine does Duncan have in May?
What is the UV index reading in May?
Average temperature in May
Duncan, IA
- Average high temperature in May: 68°F
The warmest month (with the highest average high temperature) is July (79.7°F).
The month with the lowest average high temperature is January (22.8°F).
- Average low temperature in May: 51.8°F
The month with the highest average low temperature is July (63°F).
The coldest month (with the lowest average low temperature) is January (10.4°F).
Average pressure in May
Duncan, IA
- Average pressure in May: 29.93"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed in May
Duncan, IA
- Average wind speed in May: 9.6mph
The windiest month (with the highest average wind speed) is April (11mph).
The calmest month (with the lowest average wind speed) is July (7.4mph).
Average humidity in May
Duncan, IA
- Average humidity in May: 72%
The month with the highest relative humidity is January (89%).
The month with the lowest relative humidity is October (69%).
Average rainfall in May
Duncan, IA
- Average rainfall in May: 3.15"
The wettest month (with the highest rainfall) is June (3.82").
The driest month (with the least rainfall) is January (0.94").
Average rainfall days in May
Duncan, IA
- Average rainfall days in May: 16 days
The month with the highest number of rainy days is June (17.8 days).
The month with the least rainy days is February (2.8 days).
Average snowfall in May
Duncan, IA
- Average snowfall in May: 0.35"
The month with the highest snowfall is February (5.71").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in May
Duncan, IA
- Average snowfall days in May: 0.3 days
The month with the highest number of snowfall days is January (13.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in May /
Average sunshine in May
Duncan, IA
- Average daylight in May: 14h and 4min
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 4min
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 42min).
Average sunshine days in May
Duncan, IA
- Average sunshine days in May: 13.5 days
The month with the most sunshine days is November (18.3 days).
The month with the least sunshine days is June (10.4 days).
Average UV index in May
Duncan, IA
- Average UV index in May: 5
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in May
Duncan, IA
- Average cloud cover in May: 42
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
Duncan, IA
- Average visibility in May: 6mi
The months with the highest visibility are February, March, April, May, June, August, September, October, November and December (6mi).
The months with the lowest visibility are January and July (5mi).
Duncan, Iowa, USA
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