Annual mean 14°C · wettest around July · prevailing wind W
Warmest
21.8 °C
Coldest
12.1 °C
Wettest
40%
Windiest
6.7 m/s
Prevailing
W
5.7 m/s average
When this place is good five ratings · thirty-six ten-day sections · click a cell to read it
never good
never good
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Every reading
bars actual · line feels-like, °Cchance of rain, %wind speed, m/ssky covered, %
The average temperature in Portland over the whole year is 14°C. January is the hottest month, with highs of about 22°C; July is the coldest, with lows of about 9°C. The rainy (wet) season in Portland runs from May to October, peaking in July with a 41% chance of rain on a given day. The dry season is November to April; January is the driest month, at 10%. Winds in Portland are highest in September, averaging 5.5 m/s (20 km/h), and lightest in April, at 4.5 m/s (16 km/h). The prevailing wind is from the W. The clearest skies in Portland come in January, when the sky is typically 79% covered; June is the cloudiest month, at 85%.
Month by month Portland climate by month: average temperatures year round · click a month to read it
Month
High
Low
Feels like
Chance of rain
Cloud
Wind
Being outside
Sun
Walking
January
22°C
16°C
19°C
10%
79%
4.8 m/s
67
14
70
February
21°C
15°C
18°C
12%
81%
4.8 m/s
66
12
73
March
20°C
15°C
17°C
14%
82%
4.7 m/s
64
10
76
April
18°C
13°C
14°C
20%
84%
4.5 m/s
47
2
81
May
15°C
11°C
11°C
30%
84%
4.9 m/s
20
0
75
June
13°C
9°C
9°C
35%
85%
4.7 m/s
3
0
66
July
12°C
9°C
8°C
41%
84%
5.3 m/s
1
0
58
August
13°C
9°C
8°C
35%
83%
5.3 m/s
4
0
63
September
14°C
10°C
10°C
34%
84%
5.5 m/s
12
0
65
October
16°C
11°C
12°C
27%
82%
5.4 m/s
24
1
72
November
18°C
13°C
14°C
23%
84%
5.2 m/s
35
7
72
December
19°C
14°C
16°C
15%
81%
5.1 m/s
48
8
74
High and low are the warmest and coolest of four readings a day — midnight, 6am, noon and 6pm — so a true overnight low can sit a degree or two under them. Chance of rain, cloud and wind are the day’s average; feels-like and the three ratings (each out of 100: Good from 55, Ideal from 80) are read at midday.
Seasons, and the year in short Portland weather by season
Year round, Portland has days of about 12°C at their warmest in July, its coolest month, and 22°C in January, its warmest; the coolest hours of the day run from 9°C to 16°C through the year, and the average temperature over the year is 14°C around the clock. Rain is most likely around July and least likely around January. Every figure here is a decade of observations blended into one representative year, so it reads as what this date is usually like, not a forecast for one particular day.
Portland weather in winterJune to August
High 13°CLow 9°CRain 37%
Winter in Portland has typical daily highs of about 13°C and lows of about 9°C, with a 37% chance of rain on a given day.
Portland weather in springSeptember to November
High 16°CLow 11°CRain 28%
Spring in Portland has typical daily highs of about 16°C and lows of about 11°C, with a 28% chance of rain on a given day.
Portland weather in summerDecember to February
High 21°CLow 15°CRain 13%
Summer in Portland has typical daily highs of about 21°C and lows of about 15°C, with a 13% chance of rain on a given day.
Portland weather in autumnMarch to May
High 18°CLow 13°CRain 21%
Autumn in Portland has typical daily highs of about 18°C and lows of about 13°C, with a 21% chance of rain on a given day.
When is the rainy season in Portland?
The rainy (wet) season in Portland runs from May to October, peaking in July with a 41% chance of rain on a given day. The dry season is November to April; January is the driest month, at 10%.
What time of year is Portland windiest?
Winds in Portland are highest in September, averaging 5.5 m/s (20 km/h), and lightest in April, at 4.5 m/s (16 km/h). The prevailing wind is from the W.
What is the average temperature in Portland year round?
The average temperature in Portland over the whole year is 14°C. January is the hottest month, with highs of about 22°C; July is the coldest, with lows of about 9°C.