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
May in Portland, Oregon, introduces a minor temperature shift, with average high-temperatures adjusting from April's mild 58.6°F (14.8°C) to an enjoyable 67.1°F (19.5°C). Portland observes a substantial disparity between daytime high and the average low-temperature of 44.2°F (6.8°C) during May nights.Humidity
In May, the average relative humidity is 72%.Rainfall
In May, in Portland, the rain falls for 13.8 days. Throughout May, 1.77" (45mm) of precipitation is accumulated. In Portland, Oregon, during the entire year, the rain falls for 173.1 days and collects up to 31.18" (792mm) of precipitation.Snowfall
April through October are months without snowfall.Daylight
In Portland, the average length of the day in May is 14h and 56min.On the first day of May, sunrise is at 5:57 am and sunset at 8:18 pm. On the last day of the month, sunrise is at 5:25 am and sunset at 8:51 pm PDT.
Sunshine
In Portland, the average sunshine in May is 8.7h.UV index
The average daily maximum UV index in May in Portland is 4. A UV Index estimate of 3 to 5 represents a medium health hazard from unsafe exposure to UV radiation for average individuals.Note: The maximum UV index of 4 during May leads to these instructions:
Be vigilant - A duty to shield skin and eyes from injury exists. Solar radiation is at its peak intensity during midday, so it's advisable to stay indoors or in the shade. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense.
Frequently asked questions
What is the average May temperature in Portland?
What is the average humidity in May in Portland?
How many days does it rain in May in Portland?
When it does not snow in Portland?
What is the average length of the day in May in Portland?
When are sunrise and sunset in May in Portland?
How long on average sun shines in May in Portland?
What is the UV index reading in May in Portland?
Average temperature in May
Portland, OR
- Average high temperature in May: 67.1°F
The warmest month (with the highest average high temperature) is August (81.5°F).
The month with the lowest average high temperature is December (44.1°F).
- Average low temperature in May: 44.2°F
The month with the highest average low temperature is August (55°F).
The coldest month (with the lowest average low temperature) is December (34.7°F).
Average pressure in May
Portland, OR
- 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
Portland, OR
- Average wind speed in May: 4.2mph
The windiest month (with the highest average wind speed) is January (5.8mph).
The calmest month (with the lowest average wind speed) is August (3.9mph).
Average humidity in May
Portland, OR
- Average humidity in May: 72%
The months with the highest relative humidity are January, February and December (83%).
The month with the lowest relative humidity is August (63%).
Average rainfall in May
Portland, OR
- Average rainfall in May: 1.77"
The wettest month (with the highest rainfall) is December (4.53").
The driest month (with the least rainfall) is July (0.31").
Average rainfall days in May
Portland, OR
- Average rainfall days in May: 13.8 days
The month with the highest number of rainy days is March (20.4 days).
The month with the least rainy days is July (4.9 days).
Average snowfall in May
Portland, OR
- Average snowfall in May: 0"
The month with the highest snowfall is March (1.5").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in May
Portland, OR
- Average snowfall days in May: 0 days
The month with the highest number of snowfall days is February (2.3 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
Portland, OR
- Average daylight in May: 14h and 5min
The month with the longest days is June (Average daylight: 15h and 36min).
The month with the shortest days is December (Average daylight: 8h and 48min).
- Average sunshine in May: 8h and 4min
The month with the most sunshine is August (Average sunshine: 10h and 54min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days in May
Portland, OR
- Average sunshine days in May: 14.8 days
The months with the most sunshine days are July and August (23.8 days).
The month with the least sunshine days is March (8.3 days).
Average UV index in May
Portland, OR
- 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
Portland, OR
- Average cloud cover in May: 46
The month with the most cloud cover is February (Cloud cover 58).
The month with the least cloud cover is August (Cloud cover 23).
Average visibility in May
Portland, OR
- Average visibility in May: 5mi
The months with the highest visibility are July, August and September (6mi).
The months with the lowest visibility are January, February, March, April, May, June, October, November and December (5mi).
Portland, Oregon, USA
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