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Multnomah County · Oregon

Portland, OR weather averages

NOAA climate normals for 1991-2020, measured at Portland Intl Ap, 17 km from the city centre — month by month temperature, rain and snow.

Quick answer

Portland averages a daily high of 63.2°F and a daily low of 45.7°F across the year, with 36.03 inches of precipitation. August is the warmest month at 81.1°F and December the coldest at 35.2°F.

Average annual high
63.2°FWarmest month August
Average annual low
45.7°FColdest month December
Precipitation per year
36.03 inWettest month November
Snowfall per year
4.3 in29.6 days at or below 32°F

Portland weather month by month

Normal daily high and low, precipitation and snowfall for each month, 1991-2020.

MonthHigh °FLow °FPrecip inSnow inRange
January4735.84.880.535.8 to 47 degrees
February51.336.33.662.136.3 to 51.3 degrees
March56.739.63.680.239.6 to 56.7 degrees
April61.443.12.73043.1 to 61.4 degrees
May6848.62.47048.6 to 68 degrees
June73.553.61.7053.6 to 73.5 degrees
July80.657.80.65057.8 to 80.6 degrees
August81.1580.67058 to 81.1 degrees
September75.853.11.47053.1 to 75.8 degrees
October63.8463046 to 63.8 degrees
November52.840.55.630.240.5 to 52.8 degrees
December45.635.25.491.335.2 to 45.6 degrees

Source: NOAA NCEI, U.S. Climate Normals 1991-2020 — station USW00024229, Portland Intl Ap · rates as published for 1991-2020 normals

How to read Portland climate normals

What a climate normal is, and what it is not.

A normal is the average of thirty years of daily observations at one station — here Portland Intl Ap, 17 km from the centre of Portland. It describes a typical year, so any single year will run warmer, cooler, wetter or drier. Readings taken at an airport on the edge of town usually sit a degree or two below a dense downtown on summer nights. Portland sees about 12 days a year at or above 90°F and about 91 days with a tenth of an inch of precipitation or more.

Other Portland data on this site.