Annual mean 13°C · wettest around January · prevailing wind S
Warmest
25.4 °C
Coldest
6.0 °C
Wettest
22%
Windiest
4.4 m/s
Prevailing
S
3.1 m/s average
When this place is good five ratings · thirty-six ten-day sections · click a cell to read it
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 13°C. August is the hottest month, with highs of about 27°C; February is the coldest, with lows of about 4°C. The rainy (wet) season in Portland runs from October to April, peaking in January with a 25% chance of rain on a given day. The dry season is May to September; July is the driest month, at 3%. Winds in Portland are highest in January, averaging 3.6 m/s (13 km/h), and lightest in September, at 1.8 m/s (6 km/h). The prevailing wind is from the S. The clearest skies in Portland come in July, when the sky is typically 28% covered; February is the cloudiest month, at 73%.
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
7°C
4°C
2°C
25%
72%
3.6 m/s
0
0
23
February
7°C
4°C
3°C
22%
73%
3.0 m/s
0
0
29
March
11°C
5°C
7°C
21%
65%
2.7 m/s
5
0
52
April
15°C
7°C
11°C
17%
58%
2.5 m/s
22
1
76
May
19°C
11°C
16°C
12%
53%
2.2 m/s
57
7
84
June
23°C
14°C
19°C
9%
47%
2.2 m/s
75
17
74
July
27°C
16°C
23°C
3%
28%
2.2 m/s
84
39
54
August
27°C
15°C
24°C
3%
31%
1.9 m/s
80
44
47
September
22°C
13°C
20°C
9%
46%
1.8 m/s
85
17
74
October
16°C
9°C
13°C
18%
55%
2.1 m/s
41
2
83
November
10°C
7°C
7°C
25%
69%
2.8 m/s
5
0
51
December
7°C
4°C
3°C
24%
72%
3.3 m/s
0
0
22
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 7°C at their warmest in January, its coolest month, and 27°C in August, its warmest; the coolest hours of the day run from 4°C to 16°C through the year, and the average temperature over the year is 13°C around the clock. Rain is most likely around January and least likely around July. 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 winterDecember to February
High 7°CLow 4°CRain 24%
Winter in Portland has typical daily highs of about 7°C and lows of about 4°C, with a 24% chance of rain on a given day.
Portland weather in springMarch to May
High 15°CLow 8°CRain 17%
Spring in Portland has typical daily highs of about 15°C and lows of about 8°C, with a 17% chance of rain on a given day.
Portland weather in summerJune to August
High 26°CLow 15°CRain 5%
Summer in Portland has typical daily highs of about 26°C and lows of about 15°C, with a 5% chance of rain on a given day.
Portland weather in autumnSeptember to November
High 16°CLow 10°CRain 17%
Autumn in Portland has typical daily highs of about 16°C and lows of about 10°C, with a 17% chance of rain on a given day.
When is the rainy season in Portland?
The rainy (wet) season in Portland runs from October to April, peaking in January with a 25% chance of rain on a given day. The dry season is May to September; July is the driest month, at 3%.
What time of year is Portland windiest?
Winds in Portland are highest in January, averaging 3.6 m/s (13 km/h), and lightest in September, at 1.8 m/s (6 km/h). The prevailing wind is from the S.
What is the average temperature in Portland year round?
The average temperature in Portland over the whole year is 13°C. August is the hottest month, with highs of about 27°C; February is the coldest, with lows of about 4°C.