Climate Comfort Score
87/100
Excellent
NOAA 1991–2020 normals 55°F annual avg 2 stations
Portland, OR Climate
Pulled from NOAA NCEI 1991–2020 normals →: average temperature, precipitation, and comfort score
- 55°F
- Avg annual temp
- 87/100
- Comfort score
- 36.9"
- Annual precip
- 251d
- Growing season
30-year climate normals from 2 weather stations (1991-2020).
The climate verdict for Portland
Portland, Oregon averages 55°F a year and scores 87/100 on the comfort index - excellent, milder than 89% of U.S. cities.
- 55°F
- annual average temperature (NOAA normal)
- 87/100
- comfort score, milder than 89% of U.S. cities
- 36.9"
- annual precipitation · 4" snow
- 251 days
- growing season, frost-free days
Based on NOAA U.S. Climate Normals (1991–2020) - 30-year averages describing the typical year, not a forecast.
Avg Temperature
55°F (13°C)
Avg High
64°F
Avg Low
46°F
Annual Precip
36.9"
Annual Snow
4.2"
Comfort Score
87/100
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) 87.0%
National median (63)
PlainClimate composite, temperature mildness, humidity, precipitation, extreme-weather frequency. Excellent for the Portland area.
How Portland compares to every U.S. city
Portland's comfort score vs. all U.S. cities
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
87 Top 11% higher than 89% of 6,915 US cities
Each bar is a band; taller bars hold more US cities. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Warming context for Portland
MethodologySince 1900, U.S. land temperatures have tracked (and diverged from) the global mean - the chart below shows how. Portland's current NOAA 1991-2020 normal sits within that longer spread, and the most recent decade runs 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
Growing Season
251 days
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 | 13% | 54% |
| February | 74% | 8.1 | 15% | 45% |
| March | 71% | 7.1 | 13% | 43% |
| April | 66% | 6.9 | 13% | 35% |
| May | 66% | 6.6 | 12% | 33% |
| June | 62% | 6.8 | 22% | 22% |
| July | 61% | 7.0 | 34% | 15% |
| August | 62% | 6.2 | 29% | 15% |
| September | 70% | 5.8 | 31% | 25% |
| October | 78% | 6.8 | 18% | 44% |
| November | 80% | 8.8 | 13% | 53% |
| December | 80% | 9.4 | 9% | 60% |
What Portland's climate means for you
Portland runs 55°F a year - peaking in August, coldest in December.
- Gardeners get about 251 frost-free days, with the last spring freeze near March 13 - plan the planting calendar around it, not the regional average.
- Energy bills track 4,104 heating and 508 cooling degree days a year, higher means the furnace or AC runs more.
- Comparing places to live? Line this city up against nearby cities and the national rankings. See rankings
These are 30-year NOAA normals (1991–2020) - the typical year, not a forecast for any specific season.
Climate Guides
Climate Insight: Portland, OR
Portland, Oregon runs an annual average of 55°F, ranging from a mean daily high of 64°F to a mean daily low of 46°F, per NOAA's 1991–2020 climate normals. August is typically the warmest month of the year, while December is the coldest. Drawn from 2 weather stations, these thirty-year averages smooth out year-to-year swings into a baseline for what a typical month looks like here.
Portland averages 36.9 inches of precipitation a year, with 4.2 inches typically falling as snow, and that matters as much to daily life here as temperature does. The frost-free season averages 251 days, which directly shapes the planting calendar and growing potential for the area, with the last spring freeze near March 13 and the first fall freeze near November 19. As for energy demand, 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 87/100 (Excellent), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. Shoulder seasons bring the mildest highs and lows in the monthly tables above, summer brings August-driven heat, and winter brings December-driven cold - use that rhythm for planning. These figures are thirty-year averages rather than forecasts, so a specific year may still run warmer, cooler, wetter, or drier than what's shown.
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 87/100 (Excellent), milder than 89% of U.S. cities in the PlainClimate database.
When is the growing season in Portland? ▼
Portland has approximately 251 frost-free days per year, with the last spring freeze around March 13 and the first fall freeze around November 19.
How much energy does heating and cooling require in Portland? ▼
Portland has 4,104 heating degree days and 508 cooling degree days annually, a heating-dominated climate. See our <a href="/guides/reading-weather-data/" class="underline hover:text-brand-600">guide to reading weather data</a> for what these figures mean.
Where does this Portland climate data come from? ▼
NOAA U.S. Climate Normals v1.0.1 (1991-2020), from 2 weather stations near Portland.
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
Every figure on PlainClimate is rendered directly from NOAA 1991-2020 U.S. Climate Normals data, no number is typed in by an editor. This page draws directly on NOAA 1991-2020 U.S. Climate Normals data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.