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
Union sees an increase in the average high-temperature with the arrival of May, moving from April's refreshing 56.8°F (13.8°C) to an agreeable 68.4°F (20.2°C). Union experiences an average low-temperature reading of 52.2°F (11.2°C) throughout May.Humidity
The average relative humidity in May is 76%.Rainfall
May is the month with the most rainfall. Rain falls for 11.6 days and accumulates 1.06" (27mm) of precipitation.Snowfall
May through September are months without snowfall.Daylight
The average length of the day in May is 14h and 37min.On the first day of May, sunrise is at 6:06 am and sunset at 8:12 pm. On the last day of the month, sunrise is at 5:38 am and sunset at 8:41 pm CDT.
Sunshine
In May, the average sunshine is 8.5h.UV index
In May, the average daily maximum UV index is 5. A UV Index value of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV rays for the average person.Note: The daily maximum UV index of 5 in May interprets into the following advice:
Guard yourself - Precautionary measures against sun damage are advocated. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. Using UVA and UVB-protective sunglasses and sun-protective clothing is effective against UV radiation. Note this! The Sun's UV radiation can nearly be doubled by the reflection off snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average May temperature?
What is the average humidity in May?
What is the wettest month?
How much does it rain in May?
When it does not snow?
Does it snow in May?
How many hours of daylight does Union have in May?
What time are sunrise and sunset in May?
How many hours of sunshine does Union have in May?
What is the UV index intensity in May?
Average temperature in May
Union, IA
- Average high temperature in May: 68.4°F
The warmest month (with the highest average high temperature) is July (79.9°F).
The month with the lowest average high temperature is January (24.4°F).
- Average low temperature in May: 52.2°F
The month with the highest average low temperature is July (63.9°F).
The coldest month (with the lowest average low temperature) is January (12.2°F).
Average pressure in May
Union, 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 (29.89"Hg).
Average wind speed in May
Union, IA
- Average wind speed in May: 9.3mph
The windiest month (with the highest average wind speed) is April (10.9mph).
The calmest months (with the lowest average wind speed) are July and August (7.1mph).
Average humidity in May
Union, IA
- Average humidity in May: 76%
The month with the highest relative humidity is January (87%).
The month with the lowest relative humidity is October (71%).
Average rainfall in May
Union, IA
- Average rainfall in May: 1.06"
The wettest month (with the highest rainfall) is May (1.06").
The driest months (with the least rainfall) are January and February (0.24").
Average rainfall days in May
Union, IA
- Average rainfall days in May: 11.6 days
The month with the highest number of rainy days is May (11.6 days).
The months with the least rainy days are January and February (2 days).
Average snowfall in May
Union, IA
- Average snowfall in May: 0"
The month with the highest snowfall is February (0.79").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in May
Union, IA
- Average snowfall days in May: 0.2 days
The month with the highest number of snowfall days is January (7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in May /
Average sunshine in May
Union, IA
- Average daylight in May: 14h and 4min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in May: 8h and 3min
The month with the most sunshine is July (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).
Average sunshine days in May
Union, IA
- Average sunshine days in May: 16.3 days
The month with the most sunshine days is January (25.2 days).
The month with the least sunshine days is June (15.8 days).
Average UV index in May
Union, 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, February, October, November and December (UV index 2).
Average cloud cover in May
Union, IA
- Average cloud cover in May: 43
The month with the most cloud cover is January (Cloud cover 58).
The month with the least cloud cover is September (Cloud cover 31).
Average visibility in May
Union, IA
- Average visibility in May: 6mi
The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).
Union, Iowa, USA
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