April weather forecastRiley, OR
April
Weather in April
April in Riley, Oregon, is a fresh spring month, with an average temperature varying between 34.3°F (1.3°C) and 52.2°F (11.2°C).Temperature
The shift from March to April sees a slight increase in the average high-temperature, transitioning from a frosty 44.8°F (7.1°C) to a cool 52.2°F (11.2°C). Riley throughout April, experiences an average nighttime temperature of 34.3°F (1.3°C).Humidity
The average relative humidity in April is 60%.Rainfall
In Riley, in April, during 14.4 rainfall days, 1.3" (33mm) of precipitation is typically accumulated. Throughout the year, there are 125.1 rainfall days, and 11.26" (286mm) of precipitation is accumulated.Snowfall
April through October are months without snowfall.Daylight
The average length of the day in April is 13h and 28min.On the first day of the month, sunrise is at 6:37 am and sunset at 7:25 pm. On the last day of April, sunrise is at 5:50 am and sunset at 7:59 pm PDT.
Sunshine
In April, the average sunshine is 10.1h.UV index
In Riley, the average daily maximum UV index in April is 3. A UV Index estimate of 3 to 5 represents a medium health hazard from exposure to the Sun's UV radiation for ordinary individuals.Note: The daily maximum UV index of 3 in April interprets into the following advice:
Be mindful. Those with pale skin might receive burns in fewer than 30 minutes. Midday is the peak time for the Sun's radiation; stay in the shade and protect yourself. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in April
Riley, OR
- Average high temperature in April: 52.2°F
The warmest month (with the highest average high temperature) is July (82.9°F).
The month with the lowest average high temperature is December (33.1°F).
- Average low temperature in April: 34.3°F
The month with the highest average low temperature is August (58.1°F).
The coldest month (with the lowest average low temperature) is December (21.2°F).
Average pressure in April
Riley, OR
- Average pressure in April: 30.02"Hg
The month with the highest atmospheric pressure is January (30.22"Hg).
The month with the lowest atmospheric pressure is August (29.94"Hg).
Average wind speed in April
Riley, OR
- Average wind speed in April: 9.9mph
The windiest month (with the highest average wind speed) is April (9.9mph).
The calmest month (with the lowest average wind speed) is August (7.5mph).
Average humidity in April
Riley, OR
- Average humidity in April: 60%
The month with the highest relative humidity is December (83%).
The months with the lowest relative humidity are July and August (33%).
Average rainfall in April
Riley, OR
- Average rainfall in April: 1.3"
The wettest month (with the highest rainfall) is December (1.54").
The driest month (with the least rainfall) is July (0.16").
Average rainfall days in April
Riley, OR
- Average rainfall days in April: 14.4 days
The month with the highest number of rainy days is March (17.7 days).
The month with the least rainy days is August (3.3 days).
Average snowfall in April
Riley, OR
- Average snowfall in April: 0"
The month with the highest snowfall is December (0.87").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in April
Riley, OR
- Average snowfall days in April: 0 days
The month with the highest number of snowfall days is December (3.1 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).
Average daylight in April /
Average sunshine in April
Riley, OR
- Average daylight in April: 13h and 30min
The month with the longest days is June (Average daylight: 15h and 24min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- Average sunshine in April: 10h and 6min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 5h and 12min).
Average sunshine days in April
Riley, OR
- Average sunshine days in April: 13.3 days
The months with the most sunshine days are July and August (25.3 days).
The month with the least sunshine days is March (11.5 days).
Average UV index in April
Riley, OR
- Average UV index in April: 3
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover in April
Riley, OR
- Average cloud cover in April: 35
The month with the most cloud cover is December (Cloud cover 47).
The months with the least cloud cover are July and August (Cloud cover 9).
Average visibility in April
Riley, OR
- Average visibility in April: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).





