Portland Temperatures: Averages by Month
The numbers here tell you how hot and cold the weather usually is in Portland, Oregon during each month of the year.
The average high and low temperatures are listed below monthly and annually for Portland, in both degrees Fahrenheit and Celsius.
Maximums and minimums are only part of the temperature picture. To fill in the rest, there's information on how many days a month get above or below a given temperature.
To find out how often it rises over 70, 80 or 90 °F each month in Portland, scroll down farther. There are also monthly and yearly counts of days with cold weather.
The first set of high and low temperatures are averages for 2010 to 2019. Everything else here is based on 1991 to 2020 weather.
| High °F | Low °F | High °C | Low °C | |
|---|---|---|---|---|
| 46 | 36 | January | 8 | 2 |
| 49 | 37 | February | 10 | 3 |
| 56 | 40 | March | 13 | 4 |
| 62 | 43 | April | 17 | 6 |
| 70 | 49 | May | 21 | 9 |
| 75 | 53 | June | 24 | 12 |
| 82 | 57 | July | 28 | 14 |
| 83 | 58 | August | 28 | 15 |
| 75 | 54 | September | 24 | 12 |
| 64 | 47 | October | 18 | 8 |
| 52 | 41 | November | 11 | 5 |
| 45 | 36 | December | 7 | 2 |
| 63 | 46 | Year | 17 | 8 |
| High °F | Low °F | High °C | Low °C | |
|---|---|---|---|---|
| 46 | 37 | January | 8 | 3 |
| 51 | 37 | February | 10 | 3 |
| 56 | 40 | March | 14 | 4 |
| 62 | 43 | April | 17 | 6 |
| 69 | 48 | May | 21 | 9 |
| 74 | 53 | June | 23 | 12 |
| 82 | 57 | July | 28 | 14 |
| 82 | 57 | August | 28 | 14 |
| 76 | 53 | September | 24 | 12 |
| 64 | 46 | October | 18 | 8 |
| 52 | 41 | November | 11 | 5 |
| 46 | 36 | December | 8 | 2 |
| 63 | 46 | Year | 17 | 8 |
Days of Hot Weather in Portland
Portland has seen 90-degree weather show up as early as May and as late as September. On average one day in summer spikes into the 100s F (38 °C).
Days with temperature highs in the 80s generally show up here from May to September. Occasionally, Portland also has a day that hot in April or October.
| 70 °F 21 °C |
80 °F 27 °C |
90 °F 32 °C | |
|---|---|---|---|
| January | 0 | 0 | 0 |
| February | 0 | 0 | 0 |
| March | 1 | 0 | 0 |
| April | 6 | 1 | 0 |
| May | 13 | 5 | 1 |
| June | 20 | 8 | 2 |
| July | 29 | 19 | 6 |
| August | 29 | 19 | 6 |
| September | 22 | 10 | 2 |
| October | 6 | 1 | 0 |
| November | 0 | 0 | 0 |
| December | 0 | 0 | 0 |
| Year | 127 | 63 | 16 |
How Often Portland Has Cold Temperatures
Chilly nights at Portland, when the thermometer dips below freezing, can occur from November to April. On the coldest nights, it can drop to 20 °F (-7 °C) or below at Portland. But weather that cold only shows up here on an average of once a year.
Typically Portland has a couple of days each year when the daytime temperature doesn't climb above freezing.
| 32 °F 0 °C |
40 °F 4 °C | |
|---|---|---|
| January | 8 | 23 |
| February | 7 | 20 |
| March | 3 | 18 |
| April | 1 | 9 |
| May | 0 | 2 |
| June | 0 | 0 |
| July | 0 | 0 |
| August | 0 | 0 |
| September | 0 | 0 |
| October | 0 | 5 |
| November | 3 | 14 |
| December | 8 | 25 |
| Year | 29 | 116 |
References
Jay Lawrimore, Ron Ray, Scott Applequist, Bryant Korzeniewski, Matthew Menne. 2016. Global Summary of the Month and Year, Version 1.0. NOAA National Centers for Environmental Information.
NOAA National Centers for Environmental Information (NCEI). Climate Normals.