May weather forecastKeizer, OR
May
Weather in May
May ushers in a noticeable improvement in the atmospheric conditions in Keizer, Oregon, with the advent of the warmer, drier weather that precedes summer. Rainfall diminishes to 1.46" (37mm), indicating the transition from the rainy season to one of more dryness and warmth. Lengthier days with more sunshine allow for pleasant outdoor excursions. The weather is generally conducive for a myriad of outdoor activities. The increased daylight hours coupled with warmer temperatures mark this period as the lead-up to summer.Temperature
The start of May brings a subtle rise in the average high-temperature, moving from a mild 58.8°F (14.9°C) in April to a still refreshing 66.7°F (19.3°C). Keizer reports a considerable drop from daytime temperatures in May, recording an average nighttime figure of 42.8°F (6°C).Humidity
In May, the average relative humidity is 76%.Rainfall
In Keizer, in May, it is raining for 13.4 days, with typically 1.46" (37mm) of accumulated precipitation. In Keizer, during the entire year, the rain falls for 162.5 days and collects up to 25.08" (637mm) of precipitation.Snowfall
April through October are months without snowfall.Daylight
The average length of the day in May is 14h and 53min.On the first day of the month, sunrise is at 5:59 am and sunset at 8:18 pm. On the last day of May, in Keizer, Oregon, sunrise is at 5:28 am and sunset at 8:51 pm PDT.
Sunshine
In Keizer, the average sunshine in May is 8.6h.UV index
The average daily maximum UV index in May 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 of 4 during May translates into these guidelines:
Exercise prudence. Persons with fair skin could be burned in under 30 minutes. To prevent harmful UV exposure, minimize direct contact with the Sun around midday. Using UVA and UVB-protective sunglasses and sun-protective clothing is effective against UV radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
Keizer, OR
- Average high temperature in May: 66.7°F
The warmest month (with the highest average high temperature) is August (82°F).
The month with the lowest average high temperature is December (45.5°F).
- Average low temperature in May: 42.8°F
The month with the highest average low temperature is August (54.1°F).
The coldest month (with the lowest average low temperature) is December (34.5°F).
Average pressure in May
Keizer, OR
- Average pressure in May: 30.04"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The months with the lowest atmospheric pressure are August and September (30.01"Hg).
Average wind speed in May
Keizer, OR
- Average wind speed in May: 4.5mph
The windiest months (with the highest average wind speed) are January, March and November (5.5mph).
The calmest month (with the lowest average wind speed) is August (4.2mph).
Average humidity in May
Keizer, OR
- Average humidity in May: 76%
The months with the highest relative humidity are January, February and December (86%).
The month with the lowest relative humidity is August (65%).
Average rainfall in May
Keizer, OR
- Average rainfall in May: 1.46"
The wettest month (with the highest rainfall) is December (3.94").
The driest month (with the least rainfall) is July (0.28").
Average rainfall days in May
Keizer, OR
- Average rainfall days in May: 13.4 days
The month with the highest number of rainy days is March (19.6 days).
The month with the least rainy days is July (3.9 days).
Average snowfall in May
Keizer, OR
- Average snowfall in May: 0"
The month with the highest snowfall is February (1.18").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in May
Keizer, OR
- Average snowfall days in May: 0 days
The month with the highest number of snowfall days is February (1.8 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).
Average daylight in May /
Average sunshine in May
Keizer, 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 36min
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
Keizer, OR
- Average sunshine days in May: 16.3 days
The month with the most sunshine days is July (26.3 days).
The month with the least sunshine days is March (8.8 days).
Average UV index in May
Keizer, 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
Keizer, OR
- Average cloud cover in May: 48
The month with the most cloud cover is February (Cloud cover 60).
The month with the least cloud cover is August (Cloud cover 21).
Average visibility in May
Keizer, 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).
