May weather forecastNorth Cascades National Park, WA

May
Weather in May
The arrival of May further enhances the outdoor potential of North Cascades National Park. Temperature increases from the previous month are distinctly noticeable, and spring continues to flourish across the region. The park, warmed by increased sunshine hours, blossoms with a vibrant mix of wildflowers taking over the once snow-covered trails. Despite these changing conditions, rainfall in the park, while decreasing, still plays a significant role in the overall weather. Many prefer to visit in May due to these more favorable conditions and because the summer crowd has not yet arrived.Temperature
North Cascades National Park's transition into May is marked by a minor temperature shift, moving from a frosty 48.2°F (9°C) in April to a moderate 55.4°F (13°C). North Cascades National Park's nights in May experience an average temperature drop to a cold 35.6°F (2°C).Rainfall
In May, the rain falls for 12 days. Throughout May, 2.44" (62mm) of precipitation is accumulated. Throughout the year, there are 157 rainfall days, and 51.02" (1296mm) of precipitation is accumulated.Daylight
In May, the average length of the day is 15h and 18min.On the first day of May, sunrise is at 5:43 am and sunset at 8:21 pm. On the last day of the month, sunrise is at 5:06 am and sunset at 8:59 pm PDT.
Sunshine
The average sunshine in May is 7h.UV index
In North Cascades National Park, the average daily maximum UV index in May is 6. A UV Index value of 6 to 7 symbolizes a high health vulnerability from unprotected exposure to Sun's UV rays for ordinary individuals.Note: In May, the maximum UV index of 6 suggests these recommendations:
Elude overexposure. Fair-skinned people could get burnt in less than 20 minutes. From 10 a.m. to 4 p.m., when UV radiation is at its strongest, limit direct exposure to the Sun and note that shade structures may not provide full sun protection. Stay sun-safe with clothing that is both closely woven and worn loosely.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
North Cascades National Park, WA
- Average high temperature in May: 55°F
The warmest months (with the highest average high temperature) are July and August (70°F).
The months with the lowest average high temperature are January and December (30°F).
- Average low temperature in May: 36°F
The months with the highest average low temperature are July and August (45°F).
The coldest months (with the lowest average low temperature) are January and December (18°F).
Average rainfall in May
North Cascades National Park, WA
- Average rainfall in May: 2.4"
The wettest month (with the highest rainfall) is December (7.8").
The driest months (with the least rainfall) are July and August (1.7").
Average rainfall days in May
North Cascades National Park, WA
- Average rainfall days in May: 12 days
The month with the highest number of rainy days is December (18 days).
The month with the least rainy days is July (8 days).
Average daylight in May /
Average sunshine in May
North Cascades National Park, WA
- Average daylight in May: 15h and 18min
The month with the longest days is June (Average daylight: 16h and 6min).
The month with the shortest days is December (Average daylight: 8h and 18min).
- Average sunshine in May: 7h
The month with the most sunshine is July (Average sunshine: 9h).
The months with the least sunshine are January, November and December (Average sunshine: 2h).
Average UV index in May
North Cascades National Park, WA
- Average UV index in May: 6
The months with the highest UV index are June, July and August (UV index 7).
The months with the lowest UV index are January, November and December (UV index 1).





