September weather forecastGreenbank, WA
September
Weather in September
September, the first month of the autumn in Greenbank, is also an enjoyable month, with an average temperature fluctuating between 53.2°F (11.8°C) and 63.3°F (17.4°C).Temperature
As August transitions into September, the average high-temperature rests at a still comfortable 63.3°F (17.4°C), maintaining a close resemblance to the previous month. Greenbank experiences an average temperature drop to a fresh 53.2°F (11.8°C) during September nights.Humidity
In Greenbank, the average relative humidity in September is 79%.Rainfall
In Greenbank, in September, during 12.9 rainfall days, 1.73" (44mm) of precipitation is typically accumulated. Throughout the year, there are 183.3 rainfall days, and 23.03" (585mm) of precipitation is accumulated.Snowfall
May through October are months without snowfall.Daylight
In Greenbank, the average length of the day in September is 12h and 33min.On the first day of September, sunrise is at 6:29 am and sunset at 7:50 pm. On the last day of the month, sunrise is at 7:09 am and sunset at 6:50 pm PDT.
Sunshine
The average sunshine in September is 9.5h.UV index
The average daily maximum UV index in September in Greenbank is 4. A UV Index estimate of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV rays for the ordinary person.Note: In September, the maximum UV index of 4 translates into these guidelines:
Take precautions - Protection against sun damage is advised. It's recommended to limit sun exposure when its radiation is at its peak during midday. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Greenbank, WA
- Average high temperature in September: 63.3°F
The warmest month (with the highest average high temperature) is August (67.3°F).
The month with the lowest average high temperature is December (43.5°F).
- Average low temperature in September: 53.2°F
The month with the highest average low temperature is August (55.9°F).
The coldest month (with the lowest average low temperature) is December (37.9°F).
Average pressure in September
Greenbank, WA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.08"Hg).
The months with the lowest atmospheric pressure are March, August and September (30.01"Hg).
Average wind speed in September
Greenbank, WA
- Average wind speed in September: 4.7mph
The windiest month (with the highest average wind speed) is November (8mph).
The calmest month (with the lowest average wind speed) is August (4mph).
Average humidity in September
Greenbank, WA
- Average humidity in September: 79%
The month with the highest relative humidity is January (82%).
The month with the lowest relative humidity is July (76%).
Average rainfall in September
Greenbank, WA
- Average rainfall in September: 1.73"
The wettest month (with the highest rainfall) is November (3.19").
The driest month (with the least rainfall) is July (0.43").
Average rainfall days in September
Greenbank, WA
- Average rainfall days in September: 12.9 days
The month with the highest number of rainy days is March (20.7 days).
The month with the least rainy days is August (6.9 days).
Average snowfall in September
Greenbank, WA
- Average snowfall in September: 0"
The month with the highest snowfall is February (3.07").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Greenbank, 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
Greenbank, 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 24min).
- Average sunshine in September: 9h and 30min
The months with the most sunshine are July and August (Average sunshine: 10h and 54min).
The month with the least sunshine is January (Average sunshine: 4h and 36min).
Average sunshine days in September
Greenbank, WA
- Average sunshine days in September: 15.1 days
The month with the most sunshine days is August (23 days).
The month with the least sunshine days is February (8 days).
Average UV index in September
Greenbank, 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
Greenbank, WA
- Average cloud cover in September: 30
The months with the most cloud cover are January, February and December (Cloud cover 51).
The month with the least cloud cover is August (Cloud cover 22).
Average visibility in September
Greenbank, WA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
