May weather forecastUnion, WA
May
Weather in May
The last month of the spring, May, is a refreshing month in Union, Washington, with an average temperature fluctuating between 41.4°F (5.2°C) and 63.9°F (17.7°C).Temperature
May indicates a change in the average high-temperature, moving up from a cool 54.9°F (12.7°C) in April to a refreshing 63.9°F (17.7°C). With the onset of night in May, Union reveals a significant decrease in temperature, averaging at an icy 41.4°F (5.2°C).Humidity
The average relative humidity in May in Union, Washington, is 78%.Rainfall
In Union, during May, the rain falls for 14.3 days and regularly aggregates up to 1.97" (50mm) of precipitation. Throughout the year, in Union, there are 185.4 rainfall days, and 42.87" (1089mm) of precipitation is accumulated.Snowfall
In Union, Washington, snow does not fall in April through October.Daylight
In Union, the average length of the day in May is 15h and 8min.On the first day of the month, sunrise is at 5:54 am and sunset at 8:24 pm. On the last day of May, sunrise is at 5:19 am and sunset at 9:00 pm PDT.
Sunshine
In May, the average sunshine in Union is 8.9h.UV index
In Union, the average daily maximum UV index in May is 4. A UV Index value of 3 to 5 symbolizes a moderate threat to health from unprotected exposure to Sun's UV rays for ordinary individuals.Note: A daily maximum UV index of 4 in May translates into the following instructions:
Exercise prudence. Persons with fair skin could be burned in under 30 minutes. The Sun's radiation is especially intense around midday; try to stay in shade during this period. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
Union, WA
- Average high temperature in May: 63.9°F
The warmest month (with the highest average high temperature) is August (76.6°F).
The month with the lowest average high temperature is December (41.5°F).
- Average low temperature in May: 41.4°F
The month with the highest average low temperature is August (50.4°F).
The coldest month (with the lowest average low temperature) is February (32.7°F).
Average pressure in May
Union, WA
- Average pressure in May: 30.04"Hg
The month with the highest atmospheric pressure is January (30.08"Hg).
The month with the lowest atmospheric pressure is March (30.01"Hg).
Average wind speed in May
Union, WA
- Average wind speed in May: 3.9mph
The windiest month (with the highest average wind speed) is March (4.3mph).
The calmest month (with the lowest average wind speed) is September (3.4mph).
Average humidity in May
Union, WA
- Average humidity in May: 78%
The months with the highest relative humidity are November and December (90%).
The month with the lowest relative humidity is July (72%).
Average rainfall in May
Union, WA
- Average rainfall in May: 1.97"
The wettest month (with the highest rainfall) is January (7.24").
The driest month (with the least rainfall) is July (0.43").
Average rainfall days in May
Union, WA
- Average rainfall days in May: 14.3 days
The month with the highest number of rainy days is March (21.4 days).
The month with the least rainy days is August (6.3 days).
Average snowfall in May
Union, WA
- Average snowfall in May: 0"
The month with the highest snowfall is February (2.17").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in May
Union, WA
- Average snowfall days in May: 0 days
The month with the highest number of snowfall days is February (3.3 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in May /
Average sunshine in May
Union, WA
- Average daylight in May: 15h and 6min
The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in May: 8h and 54min
The month with the most sunshine is August (Average sunshine: 10h and 42min).
The month with the least sunshine is December (Average sunshine: 3h and 30min).
Average sunshine days in May
Union, WA
- Average sunshine days in May: 14.3 days
The month with the most sunshine days is July (21.7 days).
The month with the least sunshine days is March (7.5 days).
Average UV index in May
Union, WA
- Average UV index in May: 4
The months with the highest UV index are June and July (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in May
Union, WA
- Average cloud cover in May: 47
The months with the most cloud cover are January and December (Cloud cover 64).
The months with the least cloud cover are July and August (Cloud cover 30).
Average visibility in May
Union, WA
- Average visibility in May: 4mi
The months with the highest visibility are June, July, August and September (5mi).
The months with the lowest visibility are January, February, March, April, May, October, November and December (4mi).
