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 start of September signals a gentle decrease in the average high-temperature, transitioning from a warm 78.8°F (26°C) in August to a pleasant 70°F (21.1°C). Sunriver anticipates a pronounced temperature drop from daily highs during the nights of September, with an average low of 46°F (7.8°C).Humidity
In September, the average relative humidity is 56%.Rainfall
In Sunriver, in September, during 6.6 rainfall days, 0.83" (21mm) of precipitation is typically accumulated. Throughout the year, there are 107.1 rainfall days, and 12.17" (309mm) of precipitation is accumulated.Snowfall
Months with snowfall in Sunriver are January through May, September through December. September is the first month it typically snows. Throughout September, in the average 0.3 snowfall days, it receives 0.43" (11mm) of snow. In Sunriver, during the entire year, snow falls for 44.9 days and aggregates up to 24.57" (624mm) of snow.Daylight
The average length of the day in September is 12h and 29min.On the first day of the month, sunrise is at 6:30 am and sunset at 7:40 pm. On the last day of September, sunrise is at 7:03 am and sunset at 6:47 pm PDT.
Sunshine
The average sunshine in September is 10.8h.UV index
In September, the average daily maximum UV index is 3. A UV Index estimate of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV radiation for the average person.Note: The UV index of 3 during September leads to these advisories:
Take necessary precautions - Defending against sun damage is advocated. The Sun is at its harshest during midday; protect yourself by staying in shaded areas and minimizing exposure. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear. Take precaution! The reflection from snow can almost double the UV radiation of the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in September?
What is the average humidity in September?
How many days does it rain in September?
When does it start to snow?
How many hours of daylight does Sunriver have in September?
What time are sunrise and sunset in September?
How long on average sun shines in September?
What is the UV index intensity in September?
Average temperature in September
Sunriver, OR
- Average high temperature in September: 70°F
The warmest month (with the highest average high temperature) is July (79.5°F).
The month with the lowest average high temperature is December (35.8°F).
- Average low temperature in September: 46°F
The month with the highest average low temperature is August (52.2°F).
The coldest month (with the lowest average low temperature) is December (24.6°F).
Average pressure in September
Sunriver, OR
- Average pressure in September: 29.99"Hg
The month with the highest atmospheric pressure is January (30.17"Hg).
The month with the lowest atmospheric pressure is August (29.97"Hg).
Average wind speed in September
Sunriver, OR
- Average wind speed in September: 5.3mph
The windiest month (with the highest average wind speed) is January (7.1mph).
The calmest month (with the lowest average wind speed) is August (5.2mph).
Average humidity in September
Sunriver, OR
- Average humidity in September: 56%
The month with the highest relative humidity is December (82%).
The month with the lowest relative humidity is July (48%).
Average rainfall in September
Sunriver, OR
- Average rainfall in September: 0.83"
The wettest month (with the highest rainfall) is May (1.5").
The driest month (with the least rainfall) is July (0.35").
Average rainfall days in September
Sunriver, OR
- Average rainfall days in September: 6.6 days
The month with the highest number of rainy days is May (14 days).
The month with the least rainy days is July (4.8 days).
Average snowfall in September
Sunriver, OR
- Average snowfall in September: 0.43"
The month with the highest snowfall is February (6.65").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Sunriver, OR
- Average snowfall days in September: 0.3 days
The month with the highest number of snowfall days is March (9.5 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Sunriver, OR
- Average daylight in September: 12h and 3min
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 September: 10h and 5min
The month with the most sunshine is July (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 24min).
Average sunshine days in September
Sunriver, OR
- Average sunshine days in September: 20.4 days
The month with the most sunshine days is July (23.6 days).
The month with the least sunshine days is April (12.8 days).
Average UV index in September
Sunriver, OR
- Average UV index in September: 3
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover in September
Sunriver, OR
- Average cloud cover in September: 18
The month with the most cloud cover is December (Cloud cover 46).
The month with the least cloud cover is July (Cloud cover 10).
Average visibility in September
Sunriver, OR
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January and December (5mi).
Sunriver, Oregon, USA
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