September weather forecastRainier, OR
September
Weather in September
September, the first month of the autumn in Rainier, is also an agreeable month, with an average temperature varying between 70.7°F (21.5°C) and 47.3°F (8.5°C).Temperature
The onset of September brings a small shift in high-temperatures, falling from a warm 77.9°F (25.5°C) in August to a pleasant 70.7°F (21.5°C). Rainier, in September, experiences a marked contrast from daytime zeniths to a steady average low-temperature of 47.3°F (8.5°C).Humidity
In September, the average relative humidity is 78%.Rainfall
In Rainier, in September, it is raining for 10.8 days, with typically 1.26" (32mm) of accumulated precipitation. Throughout the year, in Rainier, there are 175.5 rainfall days, and 25.83" (656mm) of precipitation is accumulated.Snowfall
In Rainier, snow does not fall in April through October.Daylight
The average length of the day in September is 12h and 31min.On the first day of September in Rainier, sunrise is at 6:33 am and sunset at 7:49 pm. On the last day of the month, sunrise is at 7:10 am and sunset at 6:52 pm PDT.
Sunshine
In September, the average sunshine is 8.4h.UV index
In Rainier, the average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a moderate health risk from exposure to the Sun's UV rays for ordinary individuals.Note: The maximum daily UV index, 4 in September, converts into the following recommendations:
Ensure safety - Imperative it is to shield skin and eyes from damage. Avoiding the Sun's peak radiation during midday hours is essential for health and safety. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Rainier, OR
- Average high temperature in September: 70.7°F
The warmest month (with the highest average high temperature) is August (77.9°F).
The month with the lowest average high temperature is December (42.3°F).
- Average low temperature in September: 47.3°F
The month with the highest average low temperature is August (49.8°F).
The coldest month (with the lowest average low temperature) is December (32.7°F).
Average pressure in September
Rainier, OR
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The months with the lowest atmospheric pressure are August and September (30.01"Hg).
Average wind speed in September
Rainier, OR
- Average wind speed in September: 3.9mph
The windiest month (with the highest average wind speed) is January (4.8mph).
The calmest month (with the lowest average wind speed) is September (3.9mph).
Average humidity in September
Rainier, OR
- Average humidity in September: 78%
The months with the highest relative humidity are January, February, November and December (88%).
The month with the lowest relative humidity is July (72%).
Average rainfall in September
Rainier, OR
- Average rainfall in September: 1.26"
The wettest month (with the highest rainfall) is January (3.9").
The driest month (with the least rainfall) is August (0.39").
Average rainfall days in September
Rainier, OR
- Average rainfall days in September: 10.8 days
The month with the highest number of rainy days is March (20.3 days).
The month with the least rainy days is July (6.1 days).
Average snowfall in September
Rainier, OR
- Average snowfall in September: 0"
The month with the highest snowfall is January (1.26").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Rainier, OR
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (2.2 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
Rainier, OR
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 42min).
The month with the shortest days is December (Average daylight: 8h and 42min).
- Average sunshine in September: 8h and 24min
The month with the most sunshine is August (Average sunshine: 10h and 24min).
The months with the least sunshine are January, February and December (Average sunshine: 3h and 30min).
Average sunshine days in September
Rainier, OR
- Average sunshine days in September: 17 days
The month with the most sunshine days is July (22 days).
The month with the least sunshine days is March (8.9 days).
Average UV index in September
Rainier, OR
- Average UV index in September: 4
The months with the highest UV index are June and July (UV index 5).
The month with the lowest UV index is November (UV index 1).
Average cloud cover in September
Rainier, OR
- Average cloud cover in September: 44
The months with the most cloud cover are February and March (Cloud cover 65).
The month with the least cloud cover is August (Cloud cover 36).
Average visibility in September
Rainier, OR
- Average visibility in September: 4mi
The month with the highest visibility is August (5mi).
The months with the lowest visibility are January, February, March, April, May, June, July, September, October, November and December (4mi).
