September weather forecastLake Stevens, WA
September
Weather in September
The first month of the autumn, September, is also an enjoyable month in Lake Stevens, Washington, with an average temperature varying between 50°F (10°C) and 67.1°F (19.5°C).Temperature
In Lake Stevens, the average high-temperature in September slightly decreases from a pleasant 73°F (22.8°C) in August to an enjoyable 67.1°F (19.5°C). The nighttime temperature in Lake Stevens, during September, averages of 50°F (10°C).Humidity
In Lake Stevens, the average relative humidity in September is 77%.Rainfall
In September, in Lake Stevens, the rain falls for 12.3 days. Throughout September, 1.77" (45mm) of precipitation is accumulated. In Lake Stevens, during the entire year, the rain falls for 179.1 days and collects up to 29.57" (751mm) of precipitation.Snowfall
In Lake Stevens, snow does not fall in May through October.Daylight
In Lake Stevens, the average length of the day in September is 12h and 33min.On the first day of September, 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 in Lake Stevens is 9.2h.UV index
In Lake Stevens, the average daily maximum UV index in September is 3. A UV Index estimate of 3 to 5 represents a medium health hazard from exposure to the Sun's UV radiation for the ordinary person.Note: In September, the UV index of 3 transforms into the following advice:
Take necessary precautions - Defending against sun damage is advocated. Sun exposure should be minimized, especially during midday, to avoid harmful UV radiation. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Lake Stevens, WA
- Average high temperature in September: 67.1°F
The warmest month (with the highest average high temperature) is August (73°F).
The month with the lowest average high temperature is December (42.3°F).
- Average low temperature in September: 50°F
The month with the highest average low temperature is August (52.5°F).
The coldest month (with the lowest average low temperature) is December (34.7°F).
Average pressure in September
Lake Stevens, WA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The month with the lowest atmospheric pressure is August (30"Hg).
Average wind speed in September
Lake Stevens, WA
- Average wind speed in September: 4mph
The windiest months (with the highest average wind speed) are March and November (5.8mph).
The calmest month (with the lowest average wind speed) is August (3.5mph).
Average humidity in September
Lake Stevens, WA
- Average humidity in September: 77%
The months with the highest relative humidity are January and December (85%).
The month with the lowest relative humidity is July (73%).
Average rainfall in September
Lake Stevens, WA
- Average rainfall in September: 1.77"
The wettest month (with the highest rainfall) is November (4.06").
The driest month (with the least rainfall) is July (0.47").
Average rainfall days in September
Lake Stevens, WA
- Average rainfall days in September: 12.3 days
The month with the highest number of rainy days is March (19.8 days).
The month with the least rainy days is August (6.1 days).
Average snowfall in September
Lake Stevens, WA
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.68").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Lake Stevens, WA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (3.1 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
Lake Stevens, WA
- Average daylight in September: 12h and 36min
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 12min
The month with the most sunshine is August (Average sunshine: 10h and 36min).
The months with the least sunshine are January and December (Average sunshine: 4h and 12min).
Average sunshine days in September
Lake Stevens, WA
- Average sunshine days in September: 16.1 days
The month with the most sunshine days is August (23.1 days).
The months with the least sunshine days are February and November (8.6 days).
Average UV index in September
Lake Stevens, WA
- Average UV index in September: 3
The months with the highest UV index are June and 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
Lake Stevens, WA
- Average cloud cover in September: 34
The month with the most cloud cover is December (Cloud cover 57).
The month with the least cloud cover is August (Cloud cover 26).
Average visibility in September
Lake Stevens, WA
- Average visibility in September: 6mi
The months with the highest visibility are March, April, May, June, July, August, September and October (6mi).
The months with the lowest visibility are January, February, November and December (5mi).
