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
With September's onset, the weather reveals a slight temperature decrease, transitioning from a pleasant 72.7°F (22.6°C) in August to a comfortable 67.1°F (19.5°C). Clinton's temperature tends to fall to an average low of 51.4°F (10.8°C) during the nights of September.Humidity
In September, the average relative humidity is 77%.Rainfall
In Clinton, during September, the rain falls for 11.3 days and regularly aggregates up to 1.5" (38mm) of precipitation. Throughout the year, in Clinton, there are 173.1 rainfall days, and 26.02" (661mm) of precipitation is accumulated.Snowfall
May through October are months without snowfall.Daylight
In Clinton, Washington, the average length of the day in September is 12h and 33min.On the first day of September in Clinton, sunrise is at 6:28 am and sunset at 7:49 pm. On the last day of the month, sunrise is at 7:08 am and sunset at 6:49 pm PDT.
Sunshine
In September, the average sunshine is 9.4h.UV index
In Clinton, the average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV rays for the average person.Note: The maximum daily UV index of 4 during September translates into the following directions:
Put precautions into practice - Ensuring skin and eye safety is a necessity. Solar radiation peaks around mid-day, so it's wise to limit exposure to the Sun at this time. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays.
Frequently asked questions
What is the usual temperature for Clinton in September?
What is the average humidity in September in Clinton?
How many days does it rain in September in Clinton?
When it does not snow in Clinton?
How many hours of daylight does Clinton have in September?
What time are sunrise and sunset in September in Clinton?
How long on average sun shines in September in Clinton?
How high is the UV index in September in Clinton?
Average temperature in September
Clinton, WA
- Average high temperature in September: 67.1°F
The warmest month (with the highest average high temperature) is August (72.7°F).
The month with the lowest average high temperature is December (42.6°F).
- Average low temperature in September: 51.4°F
The month with the highest average low temperature is August (54°F).
The coldest month (with the lowest average low temperature) is December (35.4°F).
Average pressure in September
Clinton, WA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The months with the lowest atmospheric pressure are March, August and September (30.01"Hg).
Average wind speed in September
Clinton, WA
- Average wind speed in September: 4.2mph
The windiest month (with the highest average wind speed) is November (6.2mph).
The calmest month (with the lowest average wind speed) is August (3.6mph).
Average humidity in September
Clinton, WA
- Average humidity in September: 77%
The months with the highest relative humidity are February and December (84%).
The month with the lowest relative humidity is July (72%).
Average rainfall in September
Clinton, WA
- Average rainfall in September: 1.5"
The wettest month (with the highest rainfall) is December (3.54").
The driest month (with the least rainfall) is July (0.43").
Average rainfall days in September
Clinton, WA
- Average rainfall days in September: 11.3 days
The month with the highest number of rainy days is March (19.8 days).
The month with the least rainy days is August (6.3 days).
Average snowfall in September
Clinton, WA
- Average snowfall in September: 0"
The month with the highest snowfall is February (4.61").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Clinton, WA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (5.2 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
Clinton, WA
- Average daylight in September: 12h and 4min
The month with the longest days is June (Average daylight: 16h and 0min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in September: 9h and 2min
The month with the most sunshine is August (Average sunshine: 10h and 42min).
The month with the least sunshine is January (Average sunshine: 4h and 24min).
Average sunshine days in September
Clinton, WA
- Average sunshine days in September: 16.5 days
The month with the most sunshine days is August (22.6 days).
The month with the least sunshine days is November (9.1 days).
Average UV index in September
Clinton, 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
Clinton, WA
- Average cloud cover in September: 32
The month with the most cloud cover is December (Cloud cover 54).
The month with the least cloud cover is August (Cloud cover 25).
Average visibility in September
Clinton, WA
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).
Clinton, Washington, USA
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