September weather forecastSteptoe, WA
September
Weather in September
September, the first month of the autumn in Steptoe, is also an agreeable month, with an average temperature fluctuating between 73.2°F (22.9°C) and 52.9°F (11.6°C).Temperature
The onset of September is marked by a decrease in temperature, transitioning from a warm 83.5°F (28.6°C) in August to an agreeable 73.2°F (22.9°C). Steptoe records an average low of 52.9°F (11.6°C) throughout the nights in September.Humidity
In Steptoe, Washington, the average relative humidity in September is 46%.Rainfall
In Steptoe, in September, during 6.4 rainfall days, 0.47" (12mm) of precipitation is typically accumulated. Throughout the year, there are 120.2 rainfall days, and 14.69" (373mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, September through December. September is the first month it typically snows in Steptoe. Throughout September, in the average 0.1 snowfall days, it receives 0.2" (5mm) of snow. In Steptoe, during the entire year, snow falls for 39.6 days and aggregates up to 22.68" (576mm) of snow.Daylight
In Steptoe, the average length of the day in September is 12h and 32min.On the first day of September, sunrise is at 6:09 am and sunset at 7:28 pm. On the last day of the month, sunrise is at 6:48 am and sunset at 6:30 pm PDT.
Sunshine
In Steptoe, the average sunshine in September is 10.3h.UV index
In September, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a medium health hazard from unprotected exposure to Sun's UV rays for average individuals.Note: A maximum high daily UV index of 4 during September translates into the following directions:
Heed the precautions - Protecting the skin and eyes from damage is compulsory. Limiting sun exposure during midday hours helps in reducing the harmful effects of UV radiation. Tightly woven clothing, when worn loosely, shields effectively against the Sun. Be careful! The Sun's UV radiation can nearly be doubled by the reflective quality of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Steptoe, WA
- Average high temperature in September: 73.2°F
The warmest month (with the highest average high temperature) is August (83.5°F).
The month with the lowest average high temperature is December (34.7°F).
- Average low temperature in September: 52.9°F
The month with the highest average low temperature is August (60.4°F).
The coldest month (with the lowest average low temperature) is December (24.6°F).
Average pressure in September
Steptoe, WA
- Average pressure in September: 29.96"Hg
The month with the highest atmospheric pressure is January (30.19"Hg).
The month with the lowest atmospheric pressure is August (29.91"Hg).
Average wind speed in September
Steptoe, WA
- Average wind speed in September: 6mph
The windiest month (with the highest average wind speed) is March (8mph).
The calmest month (with the lowest average wind speed) is August (5.9mph).
Average humidity in September
Steptoe, WA
- Average humidity in September: 46%
The month with the highest relative humidity is January (85%).
The month with the lowest relative humidity is August (37%).
Average rainfall in September
Steptoe, WA
- Average rainfall in September: 0.47"
The wettest month (with the highest rainfall) is December (1.93").
The driest month (with the least rainfall) is July (0.28").
Average rainfall days in September
Steptoe, WA
- Average rainfall days in September: 6.4 days
The month with the highest number of rainy days is April (14.6 days).
The month with the least rainy days is July (4.5 days).
Average snowfall in September
Steptoe, WA
- Average snowfall in September: 0.2"
The month with the highest snowfall is February (6.69").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Steptoe, WA
- Average snowfall days in September: 0.1 days
The months with the highest number of snowfall days are February and December (9.6 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Steptoe, 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: 10h and 18min
The months with the most sunshine are July and August (Average sunshine: 12h and 0min).
The months with the least sunshine are January and December (Average sunshine: 4h and 36min).
Average sunshine days in September
Steptoe, WA
- Average sunshine days in September: 22.4 days
The month with the most sunshine days is July (24.6 days).
The month with the least sunshine days is February (12.2 days).
Average UV index in September
Steptoe, WA
- Average UV index in September: 4
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Steptoe, WA
- Average cloud cover in September: 19
The months with the most cloud cover are January and December (Cloud cover 53).
The month with the least cloud cover is July (Cloud cover 11).
Average visibility in September
Steptoe, WA
- Average visibility in September: 6mi
The months with the highest visibility are March, April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January, February and December (5mi).





