September weather forecastRivergrove, OR
September
Weather in September
The first month of the autumn, September, is still a warm month in Rivergrove, Oregon, with temperature in the range of an average low of 52°F (11.1°C) and an average high of 74.3°F (23.5°C).Temperature
As Rivergrove enters September, the average high-temperature subtly lowers from the a moderately hot 82°F (27.8°C) of August to a still warm 74.3°F (23.5°C). Despite a stark disparity with daily highs, Rivergrove records an average nighttime temperature of 52°F (11.1°C) in September.Humidity
In September, the average relative humidity is 69%.Rainfall
In Rivergrove, in September, it is raining for 10.8 days, with typically 1.57" (40mm) of accumulated precipitation. Throughout the year, there are 170.9 rainfall days, and 30.67" (779mm) of precipitation is accumulated.Snowfall
April through October are months without snowfall.Daylight
The average length of the day in September is 12h and 31min.On the first day of the month, sunrise is at 6:33 am and sunset at 7:47 pm. On the last day of September, sunrise is at 7:08 am and sunset at 6:52 pm PDT.
Sunshine
In September, the average sunshine in Rivergrove is 9.3h.UV index
The average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV radiation for the ordinary person.Note: The maximum UV index, 4 during September, leads to the following recommendations:
Make use of precautions - Suggestions to resist sunburn are communicated. Avoiding the Sun's peak radiation during midday hours is essential for health and safety. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Rivergrove, OR
- Average high temperature in September: 74.3°F
The warmest month (with the highest average high temperature) is August (82°F).
The month with the lowest average high temperature is December (44.1°F).
- Average low temperature in September: 52°F
The month with the highest average low temperature is August (55°F).
The coldest month (with the lowest average low temperature) is December (34.5°F).
Average pressure in September
Rivergrove, OR
- Average pressure in September: 30.01"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 September
Rivergrove, OR
- Average wind speed in September: 4mph
The windiest month (with the highest average wind speed) is January (5.5mph).
The calmest month (with the lowest average wind speed) is August (3.9mph).
Average humidity in September
Rivergrove, OR
- Average humidity in September: 69%
The months with the highest relative humidity are January, February and December (84%).
The month with the lowest relative humidity is August (63%).
Average rainfall in September
Rivergrove, OR
- Average rainfall in September: 1.57"
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 September
Rivergrove, OR
- Average rainfall days in September: 10.8 days
The month with the highest number of rainy days is March (19.8 days).
The month with the least rainy days is August (4.8 days).
Average snowfall in September
Rivergrove, OR
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.57").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Rivergrove, OR
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (2.3 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Rivergrove, OR
- Average daylight in September: 12h and 30min
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 September: 9h and 18min
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 6min).
Average sunshine days in September
Rivergrove, OR
- Average sunshine days in September: 18 days
The month with the most sunshine days is July (25 days).
The month with the least sunshine days is February (8.6 days).
Average UV index in September
Rivergrove, OR
- Average UV index in September: 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 September
Rivergrove, OR
- Average cloud cover in September: 32
The month with the most cloud cover is February (Cloud cover 58).
The month with the least cloud cover is August (Cloud cover 22).
Average visibility in September
Rivergrove, OR
- Average visibility in September: 6mi
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).
