Annual mean 23°C · wettest around June · prevailing wind E
Warmest
32.3 °C
Coldest
16.8 °C
Wettest
40%
Windiest
5.7 m/s
Prevailing
E
4.6 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 23°C. August is the hottest month, with highs of about 32°C; January is the coldest, with lows of about 12°C. Portland has no sharply defined rainy season: the chance of rain on a given day runs from 25% in February, the driest month, to 34% in June, the wettest. Winds in Portland are highest in April, averaging 4.8 m/s (17 km/h), and lightest in September, at 3.4 m/s (12 km/h). The prevailing wind is from the E. The clearest skies in Portland come in August, when the sky is typically 26% covered; March is the cloudiest month, at 59%.
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
17°C
12°C
14°C
32%
51%
3.8 m/s
50
6
66
February
19°C
14°C
17°C
25%
55%
4.0 m/s
58
15
57
March
22°C
18°C
21°C
31%
59%
4.4 m/s
69
26
51
April
25°C
21°C
24°C
32%
56%
4.8 m/s
64
44
31
May
28°C
24°C
29°C
33%
57%
4.8 m/s
28
62
7
June
31°C
27°C
33°C
34%
39%
4.2 m/s
4
43
1
July
31°C
27°C
35°C
28%
31%
4.2 m/s
1
31
0
August
32°C
28°C
35°C
30%
26%
3.8 m/s
2
22
0
September
31°C
26°C
33°C
33%
31%
3.4 m/s
9
41
2
October
27°C
22°C
28°C
30%
33%
3.6 m/s
29
54
20
November
22°C
17°C
21°C
32%
47%
3.6 m/s
54
38
41
December
19°C
14°C
18°C
30%
51%
3.4 m/s
60
17
60
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 17°C at their warmest in January, its coolest month, and 32°C in August, its warmest; the coolest hours of the day run from 12°C to 28°C through the year, and the average temperature over the year is 23°C around the clock. Rain is most likely around June and least likely around February. 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 18°CLow 13°CRain 29%
Winter in Portland has typical daily highs of about 18°C and lows of about 13°C, with a 29% chance of rain on a given day.
Portland weather in springMarch to May
High 25°CLow 21°CRain 32%
Spring in Portland has typical daily highs of about 25°C and lows of about 21°C, with a 32% chance of rain on a given day.
Portland weather in summerJune to August
High 31°CLow 27°CRain 31%
Summer in Portland has typical daily highs of about 31°C and lows of about 27°C, with a 31% chance of rain on a given day.
Portland weather in autumnSeptember to November
High 27°CLow 22°CRain 32%
Autumn in Portland has typical daily highs of about 27°C and lows of about 22°C, with a 32% chance of rain on a given day.
When is the rainy season in Portland?
Portland has no sharply defined rainy season: the chance of rain on a given day runs from 25% in February, the driest month, to 34% in June, the wettest.
What time of year is Portland windiest?
Winds in Portland are highest in April, averaging 4.8 m/s (17 km/h), and lightest in September, at 3.4 m/s (12 km/h). The prevailing wind is from the E.
What is the average temperature in Portland year round?
The average temperature in Portland over the whole year is 23°C. August is the hottest month, with highs of about 32°C; January is the coldest, with lows of about 12°C.