September weather forecastAriel, WA
September
Weather in September
The first month of the autumn, September, is also an agreeable month in Ariel, Washington, with an average temperature fluctuating between 47.7°F (8.7°C) and 70.2°F (21.2°C).Temperature
September brings a slight decrease in the average high-temperature, shifting from a moderately hot 77.7°F (25.4°C) in August to an agreeable 70.2°F (21.2°C). Ariel experiences a dramatic descent in temperature during September, with the average nighttime reading settling at a frosty 47.7°F (8.7°C).Humidity
In Ariel, the average relative humidity in September is 74%.Rainfall
In September, the rain falls for 11.6 days. Throughout September, 2.32" (59mm) of precipitation is accumulated. Throughout the year, in Ariel, there are 182.3 rainfall days, and 48.11" (1222mm) of precipitation is accumulated.Snowfall
In Ariel, snow does not fall in April through October.Daylight
In September, the average length of the day is 12h and 31min.On the first day of the month, sunrise is at 6:32 am and sunset at 7:47 pm. On the last day of September, in Ariel, sunrise is at 7:08 am and sunset at 6:51 pm PDT.
Sunshine
In September, the average sunshine is 8.4h.UV index
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 rays for the ordinary person.Note: A daily maximum UV index of 3 in September translates into the following instructions:
Adopt protective measures - It is advised to guard against sun damage. UV radiation is strongest from the Sun during midday; protect yourself by staying in shaded areas. 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
Ariel, WA
- Average high temperature in September: 70.2°F
The warmest month (with the highest average high temperature) is August (77.7°F).
The month with the lowest average high temperature is December (40.6°F).
- Average low temperature in September: 47.7°F
The month with the highest average low temperature is August (50.5°F).
The coldest month (with the lowest average low temperature) is December (30.7°F).
Average pressure in September
Ariel, WA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is August (30"Hg).
Average wind speed in September
Ariel, WA
- Average wind speed in September: 4.2mph
The windiest month (with the highest average wind speed) is January (6.1mph).
The calmest month (with the lowest average wind speed) is August (4.1mph).
Average humidity in September
Ariel, WA
- Average humidity in September: 74%
The month with the highest relative humidity is February (88%).
The months with the lowest relative humidity are July and August (69%).
Average rainfall in September
Ariel, WA
- Average rainfall in September: 2.32"
The wettest month (with the highest rainfall) is January (7.64").
The driest month (with the least rainfall) is July (0.43").
Average rainfall days in September
Ariel, WA
- Average rainfall days in September: 11.6 days
The month with the highest number of rainy days is March (20.8 days).
The month with the least rainy days is August (5.6 days).
Average snowfall in September
Ariel, WA
- Average snowfall in September: 0"
The month with the highest snowfall is February (4.02").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Ariel, WA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (4.2 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
Ariel, WA
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 42min).
The month with the shortest days is December (Average daylight: 8h and 42min).
- Average sunshine in September: 8h and 24min
The month with the most sunshine is August (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 3h and 12min).
Average sunshine days in September
Ariel, WA
- Average sunshine days in September: 17.1 days
The month with the most sunshine days is August (23.4 days).
The month with the least sunshine days is February (8.1 days).
Average UV index in September
Ariel, WA
- Average UV index in September: 3
The months with the highest UV index are June and July (UV index 5).
The month with the lowest UV index is November (UV index 1).
Average cloud cover in September
Ariel, WA
- Average cloud cover in September: 41
The months with the most cloud cover are February and December (Cloud cover 66).
The month with the least cloud cover is August (Cloud cover 29).
Average visibility in September
Ariel, WA
- Average visibility in September: 5mi
The months with the highest visibility are June, July, August, September and October (5mi).
The months with the lowest visibility are January, February, March, April, May, November and December (4mi).
