May weather forecastLake Oswego, OR
May
Weather in May
May boasts inviting weather in Lake Oswego with an average temperature high climbing steeply to 66.7°F (19.3°C). This month marks the boundary between spring and summer with every passing day warming up progressively. The rain starts to ease off significantly, leaving a pleasant aroma of fresh soil and bloomed flowers. The daylight period increases noticeably, with an extension of almost an hour compared to April, signaling the longer, more relaxed days of summer. Whispers of summer winds begin to replace the refreshing breezes of spring, setting the stage for the upcoming season.Temperature
The onset of May brings a minor temperature shift, with the average high-temperature moving from a moderate 58.6°F (14.8°C) in April to an enjoyable 66.7°F (19.3°C). Despite a significant deviation from daily highs, May sees an average nighttime temperature of 44.1°F (6.7°C).Humidity
The average relative humidity in May is 72%.Rainfall
In Lake Oswego, in May, it is raining for 13.9 days, with typically 1.77" (45mm) of accumulated precipitation. Throughout the year, there are 172.2 rainfall days, and 31.3" (795mm) of precipitation is accumulated.Snowfall
April through October are months without snowfall.Daylight
In Lake Oswego, the average length of the day in May is 14h and 55min.On the first day of the month, sunrise is at 5:57 am and sunset at 8:17 pm. On the last day of May, sunrise is at 5:25 am and sunset at 8:51 pm PDT.
Sunshine
In May, the average sunshine is 8.8h.UV index
The average daily maximum UV index in May in Lake Oswego, Oregon, is 4. A UV Index of 3 to 5 symbolizes a medium health hazard from unprotected exposure to Sun's UV rays for the ordinary person.Note: In May, the average maximum UV index of 4 translates into the following recommendations:
Adopt protective measures - Requirement to safeguard skin and eyes from harm exists. The Sun is most powerful around mid-day, so it's a good practice to reduce direct exposure. Employ a hat with a wide brim for robust protection, cutting UV exposure by half.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
Lake Oswego, OR
- Average high temperature in May: 66.7°F
The warmest month (with the highest average high temperature) is August (81.7°F).
The month with the lowest average high temperature is December (44.4°F).
- Average low temperature in May: 44.1°F
The month with the highest average low temperature is August (54.5°F).
The coldest month (with the lowest average low temperature) is December (34.7°F).
Average pressure in May
Lake Oswego, 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
Lake Oswego, OR
- Average wind speed in May: 4.2mph
The windiest month (with the highest average wind speed) is January (6mph).
The calmest month (with the lowest average wind speed) is August (3.7mph).
Average humidity in May
Lake Oswego, OR
- Average humidity in May: 72%
The month with the highest relative humidity is February (84%).
The month with the lowest relative humidity is August (63%).
Average rainfall in May
Lake Oswego, OR
- Average rainfall in May: 1.77"
The wettest month (with the highest rainfall) is December (4.57").
The driest month (with the least rainfall) is July (0.31").
Average rainfall days in May
Lake Oswego, OR
- Average rainfall days in May: 13.9 days
The month with the highest number of rainy days is March (20.4 days).
The month with the least rainy days is July (4.8 days).
Average snowfall in May
Lake Oswego, OR
- Average snowfall in May: 0"
The month with the highest snowfall is March (1.46").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in May
Lake Oswego, 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
Lake Oswego, OR
- Average daylight in May: 14h and 54min
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 48min
The month with the most sunshine is August (Average sunshine: 11h and 0min).
The month with the least sunshine is February (Average sunshine: 4h and 12min).
Average sunshine days in May
Lake Oswego, OR
- Average sunshine days in May: 14.7 days
The month with the most sunshine days is July (23.9 days).
The month with the least sunshine days is February (8.3 days).
Average UV index in May
Lake Oswego, 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
Lake Oswego, OR
- Average cloud cover in May: 46
The month with the most cloud cover is February (Cloud cover 57).
The month with the least cloud cover is August (Cloud cover 22).
Average visibility in May
Lake Oswego, OR
- Average visibility in May: 5mi
The months with the highest visibility are July, August, September and October (6mi).
The months with the lowest visibility are January, February, March, April, May, June, November and December (5mi).
