Climateby Month

Portland, OR climate by month

NOAA 1991-2020 normals · 32 ft elevation

Portland has warm summers and chilly winters. Highs peak at 81°F in August and fall to 46°F in December. The wettest month is December (about 19 wet days) and the driest is July (about 4). Normal snowfall is about 4.2 in a year. By our comfort score the best month is June.

Warmest month
81°F
August normal high
Coldest month
37°F
January normal low
Wet days a year
156
36.9 in of precipitation
Snow a year
4.2 in
normal snowfall

How warm is Portland?

Normal highs range from 46°F in December to 81°F in August.

30°40°50°60°70°80°90° January: normal high 47°F (8°C), low 37°F (3°C) February: normal high 51°F (11°C), low 39°F (4°C) March: normal high 56°F (13°C), low 41°F (5°C) April: normal high 61°F (16°C), low 44°F (7°C) May: normal high 68°F (20°C), low 49°F (9°C) June: normal high 73°F (23°C), low 53°F (12°C) July: normal high 80°F (27°C), low 58°F (14°C) August: normal high 81°F (27°C), low 59°F (15°C) 81° 59° September: normal high 75°F (24°C), low 55°F (13°C) October: normal high 63°F (17°C), low 48°F (9°C) November: normal high 52°F (11°C), low 42°F (6°C) December: normal high 46°F (8°C), low 37°F (3°C) 46° 37° JFMAMJJASOND

Bars run from the normal low to the normal high for each month.

How rainy is Portland?

December has the most wet days (about 19); the year brings about 37 in of precipitation.

January: 19 wet days February: 16 wet days March: 18 wet days April: 17 wet days May: 13 wet days June: 9 wet days July: 4 wet days 4 August: 4 wet days September: 7 wet days October: 14 wet days November: 18 wet days December: 19 wet days 19 JFMAMJJASOND

Wet day: at least 0.01 in of rain or melted snow, counted from daily records 1991-2020.

How much does it snow?

Normal snowfall is 4.2 in a year, most of it in January.

January: 1.7 in of snow 1.7 February: 1.2 in of snow March: 0.1 in of snow April: 0.0 in of snow 0.0 May: 0.0 in of snow June: 0.0 in of snow July: 0.0 in of snow August: 0.0 in of snow September: 0.0 in of snow October: 0.0 in of snow November: 0.0 in of snow December: 1.2 in of snow JFMAMJJASOND

How humid is Portland?

Muggy days (dew point 65°F or higher) are rare in any month.

January: 0 muggy days 0 February: 0 muggy days March: 0 muggy days April: 0 muggy days May: 0 muggy days June: 0 muggy days July: 0 muggy days 0 August: 0 muggy days September: 0 muggy days October: 0 muggy days November: 0 muggy days December: 0 muggy days JFMAMJJASOND

Muggy day: daily mean dew point of 65°F or higher, from hourly observations 1991-2020 at Portland International Airport, 6.0 mi NNE of the city center.

How much daylight?

Daylight ranges from about 8.8 hours in December to 15.6 hours in June.

January: 9.2 hours of daylight February: 10.4 hours of daylight March: 11.9 hours of daylight April: 13.5 hours of daylight May: 14.9 hours of daylight June: 15.6 hours of daylight 15.6 July: 15.3 hours of daylight August: 14.1 hours of daylight September: 12.5 hours of daylight October: 10.9 hours of daylight November: 9.5 hours of daylight December: 8.8 hours of daylight 8.8 JFMAMJJASOND
See all numbers
Monthly climate normals and day counts for Portland, 1991-2020
MonthHighLowPrecip.Wet daysSnowMuggy daysDaylight
January 47°F37°F 5.0 in19 1.7 in 0 9.2 h
February 51°F39°F 3.7 in16 1.2 in 0 10.4 h
March 56°F41°F 4.0 in18 0.1 in 0 11.9 h
April 61°F44°F 2.9 in17 0.0 in 0 13.5 h
May 68°F49°F 2.5 in13 0.0 in 0 14.9 h
June 73°F53°F 1.6 in9 0.0 in 0 15.6 h
July 80°F58°F 0.5 in4 0.0 in 0 15.3 h
August 81°F59°F 0.5 in4 0.0 in 0 14.1 h
September 75°F55°F 1.5 in7 0.0 in 0 12.5 h
October 63°F48°F 3.4 in14 0.0 in 0 10.9 h
November 52°F42°F 5.5 in18 0.0 in 0 9.5 h
December 46°F37°F 5.8 in19 1.2 in 0 8.8 h

High and low: NOAA 1991-2020 normal daily high and low. Wet days: at least 0.01 in of rain or melted snow. Muggy days: daily mean dew point 65°F or higher.

Best months to visit Portland

By our comfort score, the best month is June.

Comfort score by month (0-100) and its parts, in days per month
MonthScoreComfortableNotable rainHot or cold
Jan 330125
Feb 39092
Mar 484110
Apr 59890
May 711471
Jun 801951
Jul 761624
Aug 731524
Sep 741841
Oct 571180
Nov 361121
Dec 310135

Score = 40 × share of comfortable days + 25 × share of days without notable rain + 20 × share of days neither hot (90°F+) nor cold (high 40°F or below) + 15 × daylight. How the score works.

Frost dates in Portland

The last spring frost typically comes around Mar 13, and the first fall frost around Nov 19, leaving 247 frost-free days in a typical year.

Frost and freeze dates for Portland
Typical date1 year in 10
Last spring frost (32°F)Mar 13after Apr 1
First fall frost (32°F)Nov 19before Oct 29
Last hard freeze (28°F)Feb 16after Mar 6
First hard freeze (28°F)Dec 5before Nov 12
Frost-free season247 daysunder 219 days

"Typical" is the date with a 50% chance of a later spring frost (or earlier fall frost). Planting after the "1 year in 10" spring date gives a 90% chance of no further frost. The Old Farmer's Almanac publishes 30% dates, which fall between our typical and 1-in-10 dates.

Station: Portland Intl Airport (USW00024229), NOAA 1991-2020 freeze probabilities. Frost dates for every city in Oregon.

Hottest and coldest readings, 1991-2020

The highest reading was 105°F (July 29, 2009, and 1 other day); the lowest was 14°F (December 8, 2013).

From the temperature station's daily records with NOAA quality flags removed. Not an all-time record.

Near Portland

Similar climates elsewhere

Where the numbers come from

  • Temperature: Portland Kgw-Tv (USC00356749), 0.7 mi WSW of the city center, 159 ft (127 ft higher than the city). NOAA normals and daily records, 1991-2020.
  • Rain, snowfall, snow depth, frost dates and humidity and wind by hour: Portland Intl Airport (USW00024229), 5.9 mi NE of the city center, 19 ft . NOAA normals and daily records, 1991-2020.
  • Daily humidity and wind: Portland International Airport (726980-24229), 6.0 mi NNE of the city center, 22 ft . Hourly observations, 1991-2020.
  • Not available for this location: cloud cover (no station close enough or similar enough in elevation).

Distances from the city center (USGS). Methodology · Report an error