September weather forecastOpportunity, WA
September
Weather in September
The first month of the autumn, September, is also an agreeable month in Opportunity, Washington, with an average temperature varying between 48.2°F (9°C) and 72.5°F (22.5°C).Temperature
September involves a decrease in temperature, down from a moderately hot 83.3°F (28.5°C) in August to an agreeable 72.5°F (22.5°C). Opportunity anticipates a stark contrast in temperature during September nights, with an average low of 48.2°F (9°C).Humidity
In Opportunity, the average relative humidity in September is 52%.Rainfall
In Opportunity, during September, the rain falls for 7.9 days and regularly aggregates up to 0.63" (16mm) of precipitation. Throughout the year, in Opportunity, there are 125.4 rainfall days, and 17.28" (439mm) of precipitation is accumulated.Snowfall
January through May, September through December are months with snowfall. September is the first month it typically snows. Throughout September, in the average 0.2 snowfall days, it receives 0.35" (9mm) of snow. In Opportunity, during the entire year, snow falls for 56.4 days and aggregates up to 37.4" (950mm) of snow.Daylight
The average length of the day in September in Opportunity, Washington, is 12h and 33min.On the first day of the month, sunrise is at 6:08 am and sunset at 7:28 pm. On the last day of September, in Opportunity, sunrise is at 6:47 am and sunset at 6:29 pm PDT.
Sunshine
The average sunshine in September is 10.1h.UV index
In September, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a moderate health risk from unsafe exposure to UV radiation for the average person.Note: A daily high UV index of 4 in September leads to these guidelines:
Be mindful. Those with pale skin might receive burns in fewer than 30 minutes. Limiting exposure to the direct Sun during midday hours can help prevent harmful UV radiation effects. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes. Forewarned is forearmed! The Sun's UV radiation can be almost doubled in intensity by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Opportunity, WA
- Average high temperature in September: 72.5°F
The warmest month (with the highest average high temperature) is August (83.3°F).
The month with the lowest average high temperature is December (32°F).
- Average low temperature in September: 48.2°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 (21.9°F).
Average pressure in September
Opportunity, 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
Opportunity, WA
- Average wind speed in September: 4.9mph
The windiest month (with the highest average wind speed) is April (6.1mph).
The calmest month (with the lowest average wind speed) is December (4.7mph).
Average humidity in September
Opportunity, WA
- Average humidity in September: 52%
The month with the highest relative humidity is January (91%).
The month with the lowest relative humidity is August (43%).
Average rainfall in September
Opportunity, WA
- Average rainfall in September: 0.63"
The wettest month (with the highest rainfall) is January (2.28").
The driest months (with the least rainfall) are July and August (0.35").
Average rainfall days in September
Opportunity, WA
- Average rainfall days in September: 7.9 days
The month with the highest number of rainy days is March (16 days).
The month with the least rainy days is July (5.1 days).
Average snowfall in September
Opportunity, WA
- Average snowfall in September: 0.35"
The month with the highest snowfall is January (10.51").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Opportunity, WA
- Average snowfall days in September: 0.2 days
The month with the highest number of snowfall days is December (13.9 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Opportunity, WA
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in September: 10h and 6min
The month with the most sunshine is August (Average sunshine: 12h and 0min).
The months with the least sunshine are January and December (Average sunshine: 3h and 48min).
Average sunshine days in September
Opportunity, WA
- Average sunshine days in September: 20.8 days
The month with the most sunshine days is July (24.3 days).
The month with the least sunshine days is March (10.3 days).
Average UV index in September
Opportunity, WA
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Opportunity, WA
- Average cloud cover in September: 21
The month with the most cloud cover is January (Cloud cover 62).
The months with the least cloud cover are July and August (Cloud cover 13).
Average visibility in September
Opportunity, WA
- Average visibility in September: 6mi
The months with the highest visibility are April, May, June, July, August, September and October (6mi).
The months with the lowest visibility are January, February and December (4mi).
