September weather forecastEast Selah, WA
September
Weather in September
The first month of the autumn, September, is still a warm month in East Selah, Washington, with temperature in the range of an average high of 74.1°F (23.4°C) and an average low of 51.8°F (11°C).Temperature
A subtle decrease in the average high-temperature marks September, falling from August's moderately hot 85.1°F (29.5°C) to a still warm 74.1°F (23.4°C). Despite the significant gap from daytime peaks, East Selah experiences an average low-temperature of 51.8°F (11°C) in September.Humidity
In East Selah, Washington, the average relative humidity in September is 50%.Rainfall
In September, the rain falls for 4.8 days. Throughout September, 0.28" (7mm) of precipitation is accumulated. In East Selah, during the entire year, the rain falls for 87.6 days and collects up to 5.94" (151mm) of precipitation.Snowfall
Months with snowfall are January through April, September, November and December. September is the first month it typically snows. Throughout September, in the average 0.1 snowfall days, it receives 0.12" (3mm) of snow. Throughout the year, there are 19.9 snowfall days, and 8.62" (219mm) of snow is accumulated.Daylight
In September, the average length of the day is 12h and 32min.On the first day of the month, sunrise is at 6:22 am and sunset at 7:40 pm. On the last day of September, in East Selah, sunrise is at 7:00 am and sunset at 6:42 pm PDT.
Sunshine
In September, the average sunshine is 11.1h.UV index
In East Selah, the average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a medium vulnerability from unprotected exposure to Sun's UV rays for ordinary individuals.Note: An average maximum UV index of 4 in September leads to these recommendations:
Undertake precautions - Guarding against sun damage is counselled. Sun exposure should be minimized, especially during midday, to avoid harmful UV radiation. Sunglasses providing both UVA and UVB protection are non-negotiable on sunlit days. Notice! The UV radiation of the Sun can be intensified nearly twofold due to the reflective quality of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
East Selah, WA
- Average high temperature in September: 74.1°F
The warmest month (with the highest average high temperature) is August (85.1°F).
The month with the lowest average high temperature is December (36°F).
- Average low temperature in September: 51.8°F
The month with the highest average low temperature is August (58.8°F).
The coldest month (with the lowest average low temperature) is December (23.9°F).
Average pressure in September
East Selah, WA
- Average pressure in September: 29.97"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is August (29.93"Hg).
Average wind speed in September
East Selah, WA
- Average wind speed in September: 6.1mph
The windiest month (with the highest average wind speed) is June (7.4mph).
The calmest month (with the lowest average wind speed) is December (4.2mph).
Average humidity in September
East Selah, WA
- Average humidity in September: 50%
The month with the highest relative humidity is January (83%).
The months with the lowest relative humidity are July and August (41%).
Average rainfall in September
East Selah, WA
- Average rainfall in September: 0.28"
The wettest month (with the highest rainfall) is December (0.87").
The driest month (with the least rainfall) is July (0.08").
Average rainfall days in September
East Selah, WA
- Average rainfall days in September: 4.8 days
The month with the highest number of rainy days is March (10.8 days).
The month with the least rainy days is July (2.3 days).
Average snowfall in September
East Selah, WA
- Average snowfall in September: 0.12"
The month with the highest snowfall is December (3.07").
The months with the least snowfall are May, June, July, August and October (0").
Average snowfall days in September
East Selah, WA
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is December (5.7 days).
The months with the least snowfall days are May, June, July, August and October (0 days).
Average daylight in September /
Average sunshine in September
East Selah, WA
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 48min).
The month with the shortest days is December (Average daylight: 8h and 36min).
- Average sunshine in September: 11h and 6min
The months with the most sunshine are July and August (Average sunshine: 12h and 6min).
The month with the least sunshine is January (Average sunshine: 5h and 30min).
Average sunshine days in September
East Selah, WA
- Average sunshine days in September: 23.2 days
The month with the most sunshine days is July (27.6 days).
The month with the least sunshine days is February (15.5 days).
Average UV index in September
East Selah, WA
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
East Selah, WA
- Average cloud cover in September: 15
The month with the most cloud cover is January (Cloud cover 40).
The months with the least cloud cover are July and August (Cloud cover 9).
Average visibility in September
East Selah, 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).





