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
The arrival of September suggests a slight decrease in the average high-temperature, moving from a warm 81.1°F (27.3°C) in August to a still moderately hot 73.6°F (23.1°C). Clackamas undergoes a major shift from daytime highs, averaging a fresh 50.5°F (10.3°C) during the night in September.Humidity
In Clackamas, the average relative humidity in September is 69%.Rainfall
In Clackamas, in September, during 9.5 rainfall days, 1.5" (38mm) of precipitation is typically accumulated. Throughout the year, in Clackamas, there are 169.9 rainfall days, and 32.76" (832mm) of precipitation is accumulated.Snowfall
In Clackamas, snow does not fall in April through October.Daylight
In September, the average length of the day in Clackamas is 12h and 31min.On the first day of September in Clackamas, sunrise is at 6:32 am and sunset at 7:47 pm. On the last day of the month, sunrise is at 7:08 am and sunset at 6:51 pm PDT.
Sunshine
In September, the average sunshine in Clackamas, Oregon, is 9.4h.UV index
The average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a moderate threat to health from unprotected exposure to Sun's UV rays for the ordinary person.Note: A maximum UV index of 4 in September translates into the following recommendations:
Preventative actions are necessary - The mandate to avoid skin and eye damage is in place. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes.
Frequently asked questions
What is the temperature in September in Clackamas?
What is the average humidity in September in Clackamas?
How many days does it rain in September in Clackamas?
When it does not snow in Clackamas?
What is the average length of the day in September in Clackamas?
When is the sunrise / sunset in September in Clackamas?
How many hours of sunshine does Clackamas have in September?
What is the UV index intensity in September in Clackamas?
Average temperature in September
Clackamas, OR
- Average high temperature in September: 73.6°F
The warmest month (with the highest average high temperature) is August (81.1°F).
The month with the lowest average high temperature is December (44.4°F).
- Average low temperature in September: 50.5°F
The month with the highest average low temperature is August (54°F).
The coldest month (with the lowest average low temperature) is December (34.3°F).
Average pressure in September
Clackamas, OR
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.12"Hg).
The month with the lowest atmospheric pressure is August (30"Hg).
Average wind speed in September
Clackamas, OR
- Average wind speed in September: 3.9mph
The windiest month (with the highest average wind speed) is January (6mph).
The calmest month (with the lowest average wind speed) is August (3.5mph).
Average humidity in September
Clackamas, OR
- Average humidity in September: 69%
The month with the highest relative humidity is February (84%).
The month with the lowest relative humidity is August (64%).
Average rainfall in September
Clackamas, OR
- Average rainfall in September: 1.5"
The wettest month (with the highest rainfall) is December (5.16").
The driest month (with the least rainfall) is July (0.24").
Average rainfall days in September
Clackamas, OR
- Average rainfall days in September: 9.5 days
The month with the highest number of rainy days is March (20.3 days).
The month with the least rainy days is August (4 days).
Average snowfall in September
Clackamas, OR
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.5").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Clackamas, OR
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (2.3 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Clackamas, OR
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 36min).
The month with the shortest days is December (Average daylight: 8h and 48min).
- Average sunshine in September: 9h and 2min
The month with the most sunshine is August (Average sunshine: 11h and 6min).
The month with the least sunshine is February (Average sunshine: 4h and 18min).
Average sunshine days in September
Clackamas, OR
- Average sunshine days in September: 19 days
The month with the most sunshine days is July (26.2 days).
The month with the least sunshine days is February (8.1 days).
Average UV index in September
Clackamas, OR
- Average UV index in September: 4
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
Clackamas, OR
- Average cloud cover in September: 32
The month with the most cloud cover is February (Cloud cover 57).
The month with the least cloud cover is August (Cloud cover 22).
Average visibility in September
Clackamas, OR
- Average visibility in September: 6mi
The months with the highest visibility are July, August, September and October (6mi).
The months with the lowest visibility are January, February, March, April, May, June, November and December (5mi).
Clackamas, Oregon, USA
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