September weather forecastWenatchee, WA
September
Weather in September
September announces the onset of fall, with a gradual dip in temperature and increased rainfall up to 0.67" (17mm). There's a reduction in sunshine and daylight hours, complimenting the mellowing weather. The royalty of fall colors begin to mix with the abundant green, as the cityscape transforms. A drop in humidity parallels the drop in temperature, leading to cool, crisp mornings and evenings. As September concludes, the city readies itself for the impending chill of late fall and winter.Temperature
The start of September signals a decrease in the average high-temperature, transitioning from a warm 82.6°F (28.1°C) in August to a pleasant 71.2°F (21.8°C). With the onset of night in September, Wenatchee reveals a significant decrease in temperature, averaging at a frosty 47.5°F (8.6°C).Humidity
In September, the average relative humidity is 55%.Rainfall
In September, the rain falls for 6 days. Throughout September, 0.67" (17mm) of precipitation is accumulated. Throughout the year, there are 111.1 rainfall days, and 11.3" (287mm) of precipitation is accumulated.Snowfall
In Wenatchee, snow does not fall in May through October.Daylight
The average length of the day in September is 12h and 32min.On the first day of the month, sunrise is at 6:21 am and sunset at 7:40 pm. On the last day of September, in Wenatchee, sunrise is at 7:00 am and sunset at 6:41 pm PDT.
Sunshine
In September, the average sunshine is 10.8h.UV index
The average daily maximum UV index in September is 3. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for the average person.Note: In September, an average UV index of 3 transforms into the following instructions:
Be cautious. Those with fair skin can be subjected to burns in fewer than 30 minutes. Sun's radiation is most powerful around mid-day, so it's best to limit outdoor activities during this time. A hat with a broad brim is indispensable, filtering out up to half of UV rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Wenatchee, WA
- Average high temperature in September: 71.2°F
The warmest months (with the highest average high temperature) are July and August (82.6°F).
The month with the lowest average high temperature is December (32.4°F).
- Average low temperature in September: 47.5°F
The month with the highest average low temperature is August (53.6°F).
The coldest month (with the lowest average low temperature) is December (20.7°F).
Average pressure in September
Wenatchee, WA
- Average pressure in September: 29.97"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is August (29.93"Hg).
Average wind speed in September
Wenatchee, WA
- Average wind speed in September: 5mph
The windiest month (with the highest average wind speed) is June (6.1mph).
The calmest month (with the lowest average wind speed) is December (3.4mph).
Average humidity in September
Wenatchee, WA
- Average humidity in September: 55%
The month with the highest relative humidity is January (89%).
The months with the lowest relative humidity are July and August (47%).
Average rainfall in September
Wenatchee, WA
- Average rainfall in September: 0.67"
The wettest month (with the highest rainfall) is January (1.77").
The driest months (with the least rainfall) are July and August (0.24").
Average rainfall days in September
Wenatchee, WA
- Average rainfall days in September: 6 days
The month with the highest number of rainy days is March (14 days).
The month with the least rainy days is August (3.4 days).
Average snowfall in September
Wenatchee, WA
- Average snowfall in September: 0"
The month with the highest snowfall is December (4.76").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Wenatchee, WA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is December (6.9 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Wenatchee, 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 48min
The month with the most sunshine is August (Average sunshine: 12h and 6min).
The month with the least sunshine is January (Average sunshine: 4h and 36min).
Average sunshine days in September
Wenatchee, WA
- Average sunshine days in September: 22.2 days
The month with the most sunshine days is August (26.3 days).
The month with the least sunshine days is February (13.3 days).
Average UV index in September
Wenatchee, WA
- Average UV index in September: 3
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
Wenatchee, WA
- Average cloud cover in September: 18
The month with the most cloud cover is January (Cloud cover 49).
The month with the least cloud cover is August (Cloud cover 11).
Average visibility in September
Wenatchee, WA
- Average visibility in September: 6mi
The months with the highest visibility are March, April, May, June, July, August, September and October (6mi).
The months with the lowest visibility are January, February and December (4mi).
