Climate Comfort Score
82/100
Excellent
2026 data Public-data reference. official source
Portland, OR Climate
Temperature, precipitation, and comfort score from NOAA NCEI 1991-2020 normals →
30-year climate normals from 2 weather stations (1991-2020).
Portland, Oregon has an average annual temperature of 55°F and a climate comfort score of 82/100 (Excellent). Annual precipitation totals 36.9", including 4.2" of snow. Based on NOAA 30-year normals (1991–2020).
Avg Temperature
55°F (13°C)
Avg High
64°F
Avg Low
46°F
Annual Precip
36.9"
Annual Snow
4.2"
Comfort Score
82/100
Excellent
Avg Annual Temperature
55°F
30-year mean (NOAA NCEI)
Annual Precipitation
36.9"
Plus 4.2" of snow
Comfort score vs national 100-point ceiling (Portland) 82.0%
National median (≈55)
PlainClimate composite — temperature mildness, humidity, precipitation, extreme-weather frequency. Excellent for the Portland area.
Warming context for Portland
MethodologyHow the U.S. land temperature anomaly tracks against the global mean since 1900. The current NOAA 1991-2020 normal for Portland captures average conditions across the spread shown — the most recent decade is warmer than the 30-year mean.
- United States land mean (NOAA NCEI) +0.11 °C/decade
- Global anomaly (NASA GISTEMP) +0.11 °C/decade
- Paris Agreement thresholds 1.5°C / 2.0°C
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 48°F (9°C) | 36°F (2°C) | 42°F (5°C) | 5.0" | 1.7" | 8.7 | 0.0 |
| February | 52°F (11°C) | 37°F (3°C) | 44°F (7°C) | 3.7" | 1.2" | 7.2 | 0.0 |
| March | 57°F (14°C) | 40°F (4°C) | 48°F (9°C) | 4.0" | 0.1" | 2.6 | 0.0 |
| April | 62°F (17°C) | 44°F (7°C) | 53°F (12°C) | 2.9" | 0.0" | 0.3 | 0.0 |
| May | 69°F (21°C) | 49°F (10°C) | 59°F (15°C) | 2.5" | 0.0" | 0.0 | 0.4 |
| June | 74°F (24°C) | 54°F (12°C) | 64°F (18°C) | 1.6" | 0.0" | 0.0 | 1.8 |
| July | 82°F (28°C) | 59°F (15°C) | 70°F (21°C) | 0.5" | 0.0" | 0.0 | 5.0 |
| August | 82°F (28°C) | 59°F (15°C) | 71°F (21°C) | 0.5" | 0.0" | 0.0 | 5.3 |
| September | 77°F (25°C) | 54°F (12°C) | 65°F (19°C) | 1.5" | 0.0" | 0.0 | 2.1 |
| October | 64°F (18°C) | 47°F (8°C) | 56°F (13°C) | 3.4" | 0.0" | 0.4 | 0.0 |
| November | 54°F (12°C) | 41°F (5°C) | 47°F (8°C) | 5.5" | 0.0" | 4.1 | 0.0 |
| December | 47°F (8°C) | 36°F (2°C) | 42°F (5°C) | 5.8" | 1.2" | 8.4 | 0.0 |
Monthly Precipitation
Average monthly rainfall and snowfall
January 5.0"
Snow: 1.7"
18.7 days with precipitation
February 3.7"
Snow: 1.2"
15.7 days with precipitation
March 4.0"
Snow: 0.1"
17.8 days with precipitation
April 2.9"
17.4 days with precipitation
May 2.5"
13.2 days with precipitation
June 1.6"
9.2 days with precipitation
July 0.5"
3.7 days with precipitation
August 0.5"
3.6 days with precipitation
September 1.5"
6.7 days with precipitation
October 3.4"
13.5 days with precipitation
November 5.5"
18.3 days with precipitation
December 5.8"
Snow: 1.2"
19.2 days with precipitation
Frost Dates & Growing Season
First Fall Freeze
November 19
50% probability date
Last Spring Freeze
March 13
50% probability date
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
4,104
Higher = more heating needed
Cooling Degree Days
508
Higher = more cooling needed
Warmest Month
August
Coldest Month
December
Humidity & Wind
Monthly averages from hourly observations
| Month | Humidity | Wind (mph) | Clear Sky % | Overcast % |
|---|---|---|---|---|
| January | 79% | 8.5 | -6662% | -6648% |
| February | 74% | 8.1 | -1654% | -1629% |
| March | 71% | 7.1 | -4576% | -4559% |
| April | 66% | 6.9 | -821% | -801% |
| May | 66% | 6.6 | -2490% | -2475% |
| June | 62% | 6.8 | -1231% | -1230% |
| July | 61% | 7.0 | 34% | 15% |
| August | 62% | 6.2 | 29% | 15% |
| September | 70% | 5.8 | -805% | -810% |
| October | 78% | 6.8 | -4573% | -4559% |
| November | 80% | 8.8 | -3742% | -3717% |
| December | 80% | 9.4 | -7914% | -7903% |
Related Data
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Climate Guides
Climate Insight: Portland, OR
The NOAA 1991–2020 climate normals describe Portland, Oregon as a location with an annual average temperature of 55°F, ranging from a mean daily high of 64°F to a mean daily low of 46°F. August is typically the warmest month of the year, while December is the coldest. These thirty-year averages, computed from 2 weather stations, smooth out year-to-year variability and give a baseline expectation for typical conditions in any given month.
Precipitation patterns matter as much as temperature for anyone planning to live, garden, or travel here. Portland receives roughly 36.9 inches of precipitation each year, with 4.2 inches typically falling as snow. Growing-season length varies with elevation and microclimate, with the last spring freeze near March 13 and the first fall freeze near November 19. For energy use, 4,104 heating degree days and 508 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.
On PlainClimate's composite comfort index, Portland scores 82/100 (Excellent), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. Use the monthly tables above to plan around specific windows — shoulder seasons for mild highs and lows, peak summer for August-driven heat, or deep winter for December-driven cold. All figures here are thirty-year averages: any single year may run warmer, wetter, drier, or cooler than the normal, so treat them as planning guidance rather than forecasts.
Frequently Asked Questions
What is the average temperature in Portland, OR? ▼
The average annual temperature in Portland, Oregon is 55°F. The warmest month averages 82°F (28°C) and the coldest averages 36°F (2°C).
How much rain does Portland get? ▼
Portland receives 36.9 inches of precipitation annually, including 4.2 inches of snow. Based on NOAA 30-year climate normals (1991-2020).
What is the comfort score for Portland? ▼
Portland has a climate comfort score of 82/100 (Excellent). This score considers temperature mildness, humidity, precipitation, and extreme weather frequency.
When is the growing season in Portland? ▼
Growing season data is not available for Portland.
How much energy does heating and cooling require in Portland? ▼
Portland has 4,104 heating degree days and 508 cooling degree days annually. Higher heating degree days indicate greater winter energy demand, while higher cooling degree days indicate greater summer cooling needs.
Where does this Portland climate data come from? ▼
All climate data comes from NOAA U.S. Climate Normals v1.0.1, covering the 30-year period from 1991 to 2020. Data is collected from 2 weather stations. These 30-year averages are the standard reference for typical weather conditions.
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). Station: USW00024229. For informational purposes only.
Read our methodology — how this data is sourced, computed, and verified.
Related
Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainClimate Editorial
