September weather forecastBow, WA
September
Weather in September
September, the first month of the autumn in Bow, is still a refreshing month, with an average temperature varying between 51.4°F (10.8°C) and 64°F (17.8°C).Temperature
With September's arrival, Bow notes an average high-temperature of a comfortable 64°F (17.8°C), closely following the trend of the preceding month. Bow experiences a nighttime temperature average of 51.4°F (10.8°C) during September.Humidity
In Bow, the average relative humidity in September is 79%.Rainfall
In Bow, in September, it is raining for 12.1 days, with typically 2.24" (57mm) of accumulated precipitation. Throughout the year, there are 185.2 rainfall days, and 34.72" (882mm) of precipitation is accumulated.Snowfall
In Bow, snow does not fall in May through October.Daylight
In Bow, the average length of the day in September is 12h and 34min.On the first day of the month, sunrise is at 6:28 am and sunset at 7:50 pm. On the last day of September, sunrise is at 7:08 am and sunset at 6:49 pm PDT.
Sunshine
The average sunshine in September is 9h.UV index
In Bow, the average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a moderate health risk from unsafe exposure to UV radiation for average individuals.Note: A maximum high UV index of 4 in September translates into the following recommendations:
Ensure safety - Imperative it is to shield skin and eyes from damage. To avoid the Sun's strongest rays, limit exposure around the mid-day period. For minimizing sun-related eye damage, always choose sunglasses with UVA and UVB coverage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Bow, WA
- Average high temperature in September: 64°F
The warmest months (with the highest average high temperature) are July and August (68.4°F).
The month with the lowest average high temperature is December (42.6°F).
- Average low temperature in September: 51.4°F
The month with the highest average low temperature is August (54.1°F).
The coldest month (with the lowest average low temperature) is February (36.1°F).
Average pressure in September
Bow, WA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The months with the lowest atmospheric pressure are March, August and September (30.01"Hg).
Average wind speed in September
Bow, WA
- Average wind speed in September: 4.5mph
The windiest month (with the highest average wind speed) is November (7.5mph).
The calmest month (with the lowest average wind speed) is August (3.7mph).
Average humidity in September
Bow, WA
- Average humidity in September: 79%
The months with the highest relative humidity are January and February (83%).
The month with the lowest relative humidity is July (75%).
Average rainfall in September
Bow, WA
- Average rainfall in September: 2.24"
The wettest month (with the highest rainfall) is November (4.96").
The driest month (with the least rainfall) is July (0.63").
Average rainfall days in September
Bow, WA
- Average rainfall days in September: 12.1 days
The month with the highest number of rainy days is March (20.8 days).
The month with the least rainy days is August (7.2 days).
Average snowfall in September
Bow, WA
- Average snowfall in September: 0"
The month with the highest snowfall is February (3.54").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Bow, WA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (3.6 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
Bow, WA
- Average daylight in September: 12h and 36min
The month with the longest days is June (Average daylight: 16h and 6min).
The month with the shortest days is December (Average daylight: 8h and 24min).
- Average sunshine in September: 9h and 0min
The months with the most sunshine are July and August (Average sunshine: 10h and 24min).
The month with the least sunshine is December (Average sunshine: 3h and 54min).
Average sunshine days in September
Bow, WA
- Average sunshine days in September: 16.3 days
The month with the most sunshine days is August (22.3 days).
The month with the least sunshine days is November (8.1 days).
Average UV index in September
Bow, WA
- Average UV index in September: 4
The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Bow, WA
- Average cloud cover in September: 34
The month with the most cloud cover is December (Cloud cover 59).
The month with the least cloud cover is August (Cloud cover 26).
Average visibility in September
Bow, WA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).





