Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
The arrival of September corresponds with a light shift in temperature, down from a warm 81.7°F (27.6°C) in August to a still moderately hot 74.3°F (23.5°C). West Slope logs a substantial downturn to a fresh 52°F (11.1°C) during September nights, a considerable shift from daytime highs.Humidity
In September, the average relative humidity is 69%.Rainfall
In September, the rain falls for 10.5 days. Throughout September, 1.54" (39mm) of precipitation is accumulated. In West Slope, during the entire year, the rain falls for 173.2 days and collects up to 30.55" (776mm) of precipitation.Snowfall
April through October are months without snowfall.Daylight
In September, the average length of the day is 12h and 31min.On the first day of September, sunrise is at 6:33 am and sunset at 7:48 pm. On the last day of the month, sunrise is at 7:09 am and sunset at 6:52 pm PDT.
Sunshine
In West Slope, the average sunshine in September is 9.2h.UV index
In September, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV radiation for average individuals.Note: In September, the UV index of 4 transforms into the following advice:
Preventative actions are necessary - Suggestions to safeguard against sun damage are in order. Limiting exposure to the direct Sun during midday hours can help prevent harmful UV radiation effects. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in West Slope in September?
What is the average humidity in September?
How many days does it rain in September?
When it does not snow?
How many hours of daylight does West Slope have in September?
When is the sunrise / sunset in September?
How many hours of sunshine does West Slope have in September?
What is the UV index intensity in September?
Average temperature in September
West Slope, OR
- Average high temperature in September: 74.3°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 (44.2°F).
- Average low temperature in September: 52°F
The month with the highest average low temperature is August (55.6°F).
The coldest month (with the lowest average low temperature) is December (34.7°F).
Average pressure in September
West Slope, 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
West Slope, OR
- Average wind speed in September: 4.1mph
The windiest month (with the highest average wind speed) is January (5.4mph).
The calmest month (with the lowest average wind speed) is August (4mph).
Average humidity in September
West Slope, OR
- Average humidity in September: 69%
The months with the highest relative humidity are February and December (84%).
The month with the lowest relative humidity is August (63%).
Average rainfall in September
West Slope, OR
- Average rainfall in September: 1.54"
The wettest month (with the highest rainfall) is December (4.61").
The driest month (with the least rainfall) is July (0.31").
Average rainfall days in September
West Slope, OR
- Average rainfall days in September: 10.5 days
The month with the highest number of rainy days is March (20.6 days).
The month with the least rainy days is August (4.6 days).
Average snowfall in September
West Slope, OR
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.61").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
West Slope, 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
West Slope, OR
- Average daylight in September: 12h and 3min
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 1min
The month with the most sunshine is August (Average sunshine: 10h and 54min).
The month with the least sunshine is February (Average sunshine: 3h and 54min).
Average sunshine days in September
West Slope, OR
- Average sunshine days in September: 17.9 days
The month with the most sunshine days is July (24.9 days).
The month with the least sunshine days is March (8.6 days).
Average UV index in September
West Slope, 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
West Slope, OR
- Average cloud cover in September: 33
The month with the most cloud cover is February (Cloud cover 60).
The month with the least cloud cover is August (Cloud cover 23).
Average visibility in September
West Slope, 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).
West Slope, Oregon, USA
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