May weather forecastHeisson, WA
May
Weather in May
The last month of the spring, May, is a comfortable month in Heisson, Washington, with an average temperature fluctuating between 42.4°F (5.8°C) and 64.9°F (18.3°C).Temperature
The arrival of May signals a slight increase in the average high-temperature, moving from a moderate 56.1°F (13.4°C) in April to an enjoyable 64.9°F (18.3°C). Heisson, after an intense day, registers a significant cooling to an average low-temperature of 42.4°F (5.8°C) throughout May.Humidity
In May, the average relative humidity is 76%.Rainfall
In Heisson, during May, the rain falls for 13.9 days and regularly aggregates up to 2.24" (57mm) of precipitation. Throughout the year, there are 177.9 rainfall days, and 40.67" (1033mm) of precipitation is accumulated.Snowfall
In Heisson, snow does not fall in April through October.Daylight
In May, the average length of the day is 14h and 58min.On the first day of the month, sunrise is at 5:55 am and sunset at 8:18 pm. On the last day of May, in Heisson, sunrise is at 5:23 am and sunset at 8:52 pm PDT.
Sunshine
The average sunshine in May is 8.5h.UV index
In May, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a medium vulnerability from unsafe exposure to UV radiation for the ordinary person.Note: The maximum UV index, 4 during May, leads to the following recommendations:
Undertake protective steps - Preventing sun damage is advised. Limiting exposure to the direct Sun during midday hours can help prevent harmful UV radiation effects. A wide-brim hat offers excellent sun protection for the eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
Heisson, WA
- Average high temperature in May: 64.9°F
The warmest month (with the highest average high temperature) is August (79.3°F).
The month with the lowest average high temperature is December (42.6°F).
- Average low temperature in May: 42.4°F
The month with the highest average low temperature is August (52°F).
The coldest month (with the lowest average low temperature) is December (32.7°F).
Average pressure in May
Heisson, WA
- Average pressure in May: 30.03"Hg
The month with the highest atmospheric pressure is January (30.12"Hg).
The month with the lowest atmospheric pressure is August (30"Hg).
Average wind speed in May
Heisson, WA
- Average wind speed in May: 4.2mph
The windiest month (with the highest average wind speed) is January (6.1mph).
The calmest month (with the lowest average wind speed) is August (3.8mph).
Average humidity in May
Heisson, WA
- Average humidity in May: 76%
The month with the highest relative humidity is February (86%).
The month with the lowest relative humidity is August (67%).
Average rainfall in May
Heisson, WA
- Average rainfall in May: 2.24"
The wettest month (with the highest rainfall) is January (6.06").
The driest month (with the least rainfall) is July (0.35").
Average rainfall days in May
Heisson, WA
- Average rainfall days in May: 13.9 days
The month with the highest number of rainy days is March (20.3 days).
The month with the least rainy days is August (5.1 days).
Average snowfall in May
Heisson, WA
- Average snowfall in May: 0"
The month with the highest snowfall is February (2.76").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in May
Heisson, WA
- Average snowfall days in May: 0 days
The month with the highest number of snowfall days is February (3.7 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
Heisson, WA
- Average daylight in May: 15h and 0min
The month with the longest days is June (Average daylight: 15h and 42min).
The month with the shortest days is December (Average daylight: 8h and 42min).
- Average sunshine in May: 8h and 30min
The month with the most sunshine is August (Average sunshine: 10h and 48min).
The months with the least sunshine are January and February (Average sunshine: 3h and 48min).
Average sunshine days in May
Heisson, WA
- Average sunshine days in May: 15.5 days
The month with the most sunshine days is July (24.1 days).
The month with the least sunshine days is February (8.2 days).
Average UV index in May
Heisson, WA
- Average UV index in May: 4
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in May
Heisson, WA
- Average cloud cover in May: 48
The month with the most cloud cover is February (Cloud cover 61).
The month with the least cloud cover is August (Cloud cover 26).
Average visibility in May
Heisson, WA
- Average visibility in May: 5mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (5mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (5mi).
