Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
September brings a drop in Trentwood's average high-temperature, falling from a moderately hot 83.3°F (28.5°C) in August to an agreeable 72.5°F (22.5°C). Trentwood observes a noteworthy temperature drop from the daily highs during September nights, with a mean temperature of 48.2°F (9°C).Humidity
In September, the average relative humidity is 52%.Rainfall
In Trentwood, during September, the rain falls for 7.9 days and regularly aggregates up to 0.63" (16mm) of precipitation. Throughout the year, 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 in Trentwood. September is the first month it typically snows. Throughout September, in the average 0.2 snowfall days, it receives 0.35" (9mm) of snow. Throughout the year, there are 56.4 snowfall days, and 37.4" (950mm) of snow is accumulated.Daylight
In September, the average length of the day in Trentwood 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, sunrise is at 6:47 am and sunset at 6:29 pm PDT.
Sunshine
In Trentwood, the average sunshine in September is 10.1h.UV index
In Trentwood, Washington, the average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a medium health hazard from unprotected exposure to Sun's UV rays for the ordinary person.Note: In September, the maximum UV index of 4 translates into these guidelines:
Make use of precautions - Suggestions to resist sunburn are communicated. Direct Sun exposure should be minimized especially during midday when radiation is most intense. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection. Take heed! Reflection from the snow can almost amplify the Sun's UV radiation by double.
Frequently asked questions
What is the usual temperature for Trentwood in September?
What is the average humidity in September in Trentwood?
How many days does it rain in September in Trentwood?
When does it start to snow in Trentwood?
What is the average length of the day in September in Trentwood?
What time are sunrise and sunset in September in Trentwood?
How long on average sun shines in September in Trentwood?
What is the UV index reading in September in Trentwood?
Average temperature in September
Trentwood, 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
Trentwood, 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
Trentwood, 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
Trentwood, 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
Trentwood, 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
Trentwood, 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
Trentwood, 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
Trentwood, 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
Trentwood, WA
- Average daylight in September: 12h and 3min
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 1min
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
Trentwood, 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
Trentwood, 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
Trentwood, 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
Trentwood, 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).
Trentwood, Washington, USA
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