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Portland Weather in September: Temperature, Precipitation, Wind

Author: Rickey Bohn
Temperature
18.4°C
65.1°F
High temperature
24°C
75.2°F
Low temperature
13.6°C
56.4°F
Feels like
18.3°C
65°F
Rainy days
11 days
Rainfall level
1.13mm
0.04 inch
Cloud coverage
50.6%
Wind speed
15.5km/h
9.6mph
Daylight time
12:31:22
UV index
4.2
1
rain
21.3°C
70.0°F
2
partly cloudy day
23.6°C
74.0°F
3
rain
19.8°C
68.0°F
4
rain
17.2°C
63.0°F
5
partly cloudy day
16.9°C
62.0°F
6
partly cloudy day
17.9°C
64.0°F
7
partly cloudy day
19.2°C
67.0°F
8
partly cloudy day
18.7°C
66.0°F
9
clear day
21.3°C
70.0°F
10
partly cloudy day
21.4°C
71.0°F
11
partly cloudy day
20.1°C
68.0°F
12
partly cloudy day
19.6°C
67.0°F
13
partly cloudy day
20.9°C
70.0°F
14
clear day
21.7°C
71.0°F
15
clear day
23.3°C
74.0°F
16
clear day
21.0°C
70.0°F
17
partly cloudy day
17.8°C
64.0°F
18
partly cloudy day
18.3°C
65.0°F
19
partly cloudy day
16.2°C
61.0°F
20
rain
16.7°C
62.0°F
21
partly cloudy day
16.2°C
61.0°F
22
clear day
18.1°C
65.0°F
23
rain
17.0°C
63.0°F
24
rain
14.9°C
59.0°F
25
rain
16.2°C
61.0°F
26
rain
16.2°C
61.0°F
27
rain
15.4°C
60.0°F
28
rain
15.2°C
59.0°F
29
rain
14.6°C
58.0°F
30
partly cloudy day
14.7°C
58.0°F

In September, Portland, United States has a warm climate with an average daily temperature of 18.4°C (65.1°F). Highs reach 24°C (75.2°F) and lows drop to 13.6°C (56.4°F). You can expect partly cloudy days to be the most common condition during this month.

September sees an increase in precipitation compared to the summer months, with an average of 1.13mm (0.04 inches) of rainfall and a 36.7% chance of precipitation. There are 11 days on average with some form of rainfall, and it is more likely to occur in the morning, covering 11.8% of the sky. September is a dry month with no snowfall expected. Winds are moderate in Portland during September, with an average speed of 15.5 km/h (9.6 mph) and gusts up to 26.3 km/h (16.3 mph). The average humidity is 63.3%, and the barometric pressure is 1016.0 mb (29.99 inHg). The average cloud cover is 50.6%, and visibility is excellent at 15.9 km (9.9 miles). The weather conditions in Portland, United States in September are generally favorable, with warm temperatures, moderate precipitation, and comfortable humidity levels. Travelers can enjoy outdoor activities and explore the city’s attractions without the crowds of the peak summer season.

What is the temperature in Portland in September?

Average air temperature in Portland is 18.4°C (65.1°F) in September. The outside temperature in Portland feels like 18.3°C (65°F) on a typical September day. The highest average temperature during sunny days is 24°C (75.2°F) and feels like 23.7°C (74.7°F). The lowest average temperature after dark is 13.6°C (56.4°F) which feels like 13.5°C (56.4°F).

Daily Temperature in Portland in September 0°C / 32.0°F 5°C / 41.0°F 10°C / 50.0°F 15°C / 59.0°F 20°C / 68.0°F 25°C / 77.0°F 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

How hot is Portland in September?

The hot temperature in September in Portland rises to 34.2°C (93.6°F) on sunny days with low cloud coverage and 63.3% humidity. During hottest days of September it feels like 32 °C (89.6°F). The average maximum temp in Portland is 24°C (89.6°F) during day time in September.

How cold is Portland in September?

The coldest temp in Portland in September drops to 8.7°C (47.7°F) during the cold nights. With 15.5km/h (9.6mph) winds and 63.3% humidity it feels like 8.7°C (47.7°F) on the coldest nights. The average minimum temperature is 13.6°C (56.4°F) during night time in September.

Does it rain in Portland in September?

Yes, it rains for 11 days in Portland, United States in September averaging 1.13 mm of precipitation. Portland has a 36.7% chance for rain throughout the entire month of September.

How much does it rain in Portland throughout September?

Portland has 1.13 mm (0.04 inch) of rain per day on average in September. It rains for an average of 11 days out of the entire month.

Is Portland windy in September?

The average speed of wind in Portland, United States during September is 15.5km/h (9.6mph) and average windgust is 26.3km/h (16.3mph). On some days in September wind can reach up to 26km/h (16.2mph).

Daily wind speed in Portland in September 0km/h (0mph) 7km/h (4mph) 14km/h (9mph) 21km/h (13mph) 28km/h (17mph) 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

What is the direction of the wind in Portland in September?

Most days of September the wind is blowing from West direction in Portland.

What are the humidity levels in Portland in September?

The average humidity levels in Portland in September are 63.3%. Daily humidity levels in Portland range from 49.3% to 82% during September.

Daily humidity levels in Portland in September 0% 21% 42% 63% 84% 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

How many hours of daylight are in Portland in September?

Portland has 12 hours 31 minutes of daylight in September on average. Sunset and sunrise times gradually change throughout the month. Sunrise in Portland in September is at 6:49:39 and the sunset is at 19:21:02.

What is the cloud coverage in Portland in September?

Clouds cover 50.6% of the sky on average throughout September in Portland. The cloud coverage ranges from 0% to 99.1% depending on the day of the month.

What is the UV level in September in Portland?

The average UV index in Portland is 4.2 in September. UV levels change throughout the month and range from 1 to 8.

What is the solar radiation in Portland in September?

The average solar radiation is 66.2 W/m2 (Watts per square meter) in Portland during September. However solar radiation levels change throughout the month and range from 24.9 W/m2 to 104.3 W/m2.

What is the solar energy during September in Portland?

The average solar energy during September in Portland is 5.7 MJ/m2 (megajoules per square metre). Solar energy ranges from 2.1 MJ/m2, to 9 MJ/m2 during September.

Are there severe weather risks in Portland in September?

Yes, there is a 10% risk for severe weather in Portland, United States in September.

What is the air pressure in Portland in September?

On average the air pressure in Portland in September is 1016 mb (millibars). Throughout the month the sea level pressure ranges from 1009.8 mb to 1019.7 mb.

What is the visibility in Portland in September?

The average daylight visibility in Portland in September is 15.9 km (9.9 miles). Depending on the precipitation the visibility ranges from 14.9 km (9.3 miles) to 16 km (9.9 miles) throughout September.

What is the dew point in Portland in September?

The average dew point in Portland during September is 10.6°C (51.1°F).

Where is the data for Portland climate in September coming from?

The climate data for Portland, Oregon, United States in September is collected from the following weather stations.

  • PORTLAND INTERNATIONAL AIRPORT, OR US
  • PORTLAND TROUTDALE AIRPORT, OR US
  • VANCOUVER PEARSON AIRPORT, WA US
  • DW6016 Milwaukie OR US
  • KPDX
  • KTTD
  • KVUO