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 shift from August to September includes a small decrease in the average high-temperature, from a moderately hot 75.7°F (24.3°C) to a pleasant 68.9°F (20.5°C). Nighttime in September brings a stark departure from the daily high, resting at an average low-temperature of 47.3°F (8.5°C).Humidity
In September, the average relative humidity is 76%.Rainfall
In Duvall, in September, during 7.9 rainfall days, 0.87" (22mm) of precipitation is typically accumulated. Throughout the year, there are 137.3 rainfall days, and 16.65" (423mm) of precipitation is accumulated.Snowfall
May through October are months without snowfall.Daylight
The average length of the day in September is 12h and 33min.On the first day of the month, sunrise is at 6:27 am and sunset at 7:47 pm. On the last day of September, sunrise is at 7:06 am and sunset at 6:48 pm PDT.
Sunshine
In Duvall, the average sunshine in September is 9h.UV index
In September, the average daily maximum UV index is 4. A UV Index of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for average individuals.Note: The daily high UV index of 4 in September translates into this advice:
Take measures. Individuals with light skin might experience burns in under 30 minutes. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses.
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 much does it rain in Duvall in September?
When it does not snow in Duvall?
How many hours of daylight does Duvall have in September?
When is the sunrise / sunset in September?
How many hours of sunshine does Duvall have in September?
How high is the UV index in September?
Average temperature in September
Duvall, WA
- Average high temperature in September: 68.9°F
The warmest month (with the highest average high temperature) is August (75.7°F).
The month with the lowest average high temperature is December (41.4°F).
- Average low temperature in September: 47.3°F
The month with the highest average low temperature is August (50.2°F).
The coldest month (with the lowest average low temperature) is December (32.2°F).
Average pressure in September
Duvall, WA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is August (30"Hg).
Average wind speed in September
Duvall, WA
- Average wind speed in September: 3.5mph
The windiest month (with the highest average wind speed) is January (5mph).
The calmest month (with the lowest average wind speed) is August (3.3mph).
Average humidity in September
Duvall, WA
- Average humidity in September: 76%
The months with the highest relative humidity are January, February and December (86%).
The month with the lowest relative humidity is July (71%).
Average rainfall in September
Duvall, WA
- Average rainfall in September: 0.87"
The wettest month (with the highest rainfall) is December (2.6").
The driest months (with the least rainfall) are July and August (0.31").
Average rainfall days in September
Duvall, WA
- Average rainfall days in September: 7.9 days
The month with the highest number of rainy days is March (15.8 days).
The month with the least rainy days is August (4.8 days).
Average snowfall in September
Duvall, WA
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.46").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Duvall, WA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (2.7 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Duvall, WA
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in September: 9h and 0min
The month with the most sunshine is August (Average sunshine: 10h and 36min).
The month with the least sunshine is December (Average sunshine: 3h and 54min).
Average sunshine days in September
Duvall, WA
- Average sunshine days in September: 19.5 days
The month with the most sunshine days is August (24.1 days).
The month with the least sunshine days is February (12.6 days).
Average UV index in September
Duvall, WA
- Average UV index in September: 4
The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Duvall, WA
- Average cloud cover in September: 37
The month with the most cloud cover is December (Cloud cover 59).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in September
Duvall, WA
- Average visibility in September: 5mi
The months with the highest visibility are July and August (6mi).
The months with the lowest visibility are January, February, March, April, November and December (4mi).
Duvall, Washington, USA
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