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
As August shifts into September, a minor alteration in temperatures is observed, with average highs reducing from a moderately hot 74.7°F (23.7°C) to an agreeable 68.2°F (20.1°C). September sees the temperature falling to a mean low of 49.1°F (9.5°C).Humidity
In September, the average relative humidity is 76%.Rainfall
In Snohomish, in September, it is raining for 8.8 days, with typically 0.83" (21mm) of accumulated precipitation. In Snohomish, during the entire year, the rain falls for 140.3 days and collects up to 15.12" (384mm) of precipitation.Snowfall
In Snohomish, snow does not fall in May through October.Daylight
The average length of the day in September is 12h and 33min.On the first day of September in Snohomish, sunrise is at 6:27 am and sunset at 7:48 pm. On the last day of the month, sunrise is at 7:07 am and sunset at 6:48 pm PDT.
Sunshine
In September, the average sunshine is 9.2h.UV index
In September, the average daily maximum UV index is 3. A UV Index value of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV radiation for the ordinary person.Note: A maximum daily UV index of 3 during September morphs into the following directions:
Be mindful. Those with pale skin might receive burns in fewer than 30 minutes. For skin protection, it's recommended to minimize Sun exposure during its peak hours around midday. Employ a hat with a wide brim for robust protection, cutting UV exposure by half.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are September temperatures?
What is the average humidity in September?
How much does it rain in September?
When it does not snow?
How many hours of daylight does Snohomish have in September?
When is the sunrise / sunset in September?
How many hours of sunshine does Snohomish have in September?
How high is the UV index in September?
Average temperature in September
Snohomish, WA
- Average high temperature in September: 68.2°F
The warmest month (with the highest average high temperature) is August (74.7°F).
The month with the lowest average high temperature is December (42.3°F).
- Average low temperature in September: 49.1°F
The month with the highest average low temperature is August (51.8°F).
The coldest month (with the lowest average low temperature) is December (33.6°F).
Average pressure in September
Snohomish, 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
Snohomish, WA
- Average wind speed in September: 3.8mph
The windiest month (with the highest average wind speed) is January (5.3mph).
The calmest month (with the lowest average wind speed) is August (3.4mph).
Average humidity in September
Snohomish, WA
- Average humidity in September: 76%
The months with the highest relative humidity are January, February, November and December (85%).
The month with the lowest relative humidity is July (72%).
Average rainfall in September
Snohomish, WA
- Average rainfall in September: 0.83"
The wettest month (with the highest rainfall) is December (2.17").
The driest month (with the least rainfall) is August (0.28").
Average rainfall days in September
Snohomish, WA
- Average rainfall days in September: 8.8 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
Snohomish, WA
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.38").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Snohomish, 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
Snohomish, 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 1min
The month with the most sunshine is August (Average sunshine: 10h and 36min).
The month with the least sunshine is December (Average sunshine: 4h and 0min).
Average sunshine days in September
Snohomish, WA
- Average sunshine days in September: 19.7 days
The month with the most sunshine days is August (24 days).
The month with the least sunshine days is April (12.3 days).
Average UV index in September
Snohomish, WA
- Average UV index in September: 3
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
Snohomish, WA
- Average cloud cover in September: 35
The month with the most cloud cover is December (Cloud cover 58).
The month with the least cloud cover is August (Cloud cover 26).
Average visibility in September
Snohomish, WA
- Average visibility in September: 6mi
The months with the highest visibility are June, July, August, September and October (6mi).
The months with the lowest visibility are January, February, March, April, May, November and December (5mi).
Snohomish, Washington, USA
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