March is one of the warmer months of the year in Portland, with average highs near 19.1°C and lows around 15.1°C (mean 17.1°C). It is one of the drier months, averaging 42 mm of rainfall and 75% relative humidity across the period.
March is one of the warmer months of the year in Portland. Across 45 years of records, the warmest March in Portland was 2013 — when the month averaged 19.3°C — while the coldest was 1987 at 15.5°C. Typical March days reach 19.1°C with nights near 15.1°C. The long-term March temperature trend is broadly flat.
March is one of the drier months in Portland, averaging 42 mm of rainfall. The wettest March on record was 1983 with 133 mm, while the driest was 2024 at 6 mm.
Relative humidity in Portland during March averages 75%. The most humid March was 2021 at 79%, and the least humid was 2013 at 70%.
March receives about 4.6 kWh/m²/day of solar energy in Portland. The sunniest March was 2024 at 5.2 kWh/m²/day, and the cloudiest was 1989 at 4.1.
Average wind speed in Portland during March is 5 m/s. The windiest March was 1995 at 5.8 m/s, while the calmest were 1992 and 1994 at 4.2 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 17.1°C | 16.7°C | 17.0°C | 17.5°C | 17.3°C | +0.2°C |
| Avg High | 19.2°C | 18.6°C | 19.0°C | 19.5°C | 19.1°C | -0.1°C |
| Avg Low | 15.0°C | 14.8°C | 15.0°C | 15.6°C | 15.5°C | +0.5°C |
| Avg Rain | 56 mm | 36 mm | 39 mm | 44 mm | 37 mm | -19 mm |
March temperatures in Portland have risen by about 0.3°C between 1981–1985 and 2021–2025.
March has ranged from a record low of 11°C (1995) to a record high of 32.5°C (1986).
Rainfall in March is one of the drier months, averaging 42 mm, with a wettest year of 133 mm.
One of the best times to visit Portland
March is one of the best times to visit Portland. Expect days averaging 19.1°C and nights around 15.1°C (mean 17.1°C) — warmer than Portland's yearly average — with moderate rainfall (42 mm), so conditions are generally comfortable for sightseeing and outdoor plans.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 20.8°C | 18.6°C | 16.5°C | 29.0°C | 14.3°C | 27 mm | 73% | 4.6 m/s | 4.8 |
| 2024 | 19.9°C | 17.9°C | 15.9°C | 30.7°C | 14.1°C | 6 mm | 72% | 4.8 m/s | 5.2 |
| 2023 | 17.7°C | 16.3°C | 14.9°C | 22.2°C | 12.7°C | 67 mm | 78% | 5.3 m/s | 4.2 |
| 2022 | 19.2°C | 17.6°C | 16.0°C | 23.8°C | 14.2°C | 50 mm | 78% | 4.6 m/s | 4.6 |
| 2021 | 18.1°C | 16.5°C | 15.0°C | 23.4°C | 12.8°C | 40 mm | 79% | 4.8 m/s | 4.6 |
| 2020 | 18.7°C | 16.8°C | 14.8°C | 25.9°C | 12.9°C | 31 mm | 75% | 5 m/s | 4.4 |
| 2019 | 19.4°C | 17.4°C | 15.3°C | 30.5°C | 12.0°C | 25 mm | 74% | 4.9 m/s | 4.6 |
| 2018 | 19.8°C | 17.8°C | 15.8°C | 27.5°C | 12.5°C | 22 mm | 71% | 5.5 m/s | 4.8 |
| 2017 | 20.7°C | 18.7°C | 16.6°C | 28.3°C | 13.6°C | 61 mm | 76% | 5.4 m/s | 4.7 |
| 2016 | 19.3°C | 17.6°C | 15.9°C | 26.7°C | 14.3°C | 38 mm | 77% | 4.8 m/s | 4.3 |
| 2015 | 18.0°C | 16.2°C | 14.4°C | 22.9°C | 12.4°C | 43 mm | 73% | 5.4 m/s | 4.6 |
| 2014 | 19.1°C | 17.3°C | 15.4°C | 28.0°C | 13.1°C | 49 mm | 75% | 4.7 m/s | 4.6 |
| 2013 🔥 | 21.7°C | 19.3°C | 16.8°C | 30.9°C | 14.1°C | 32 mm | 70% | 5.4 m/s | 4.8 |
| 2012 | 19.1°C | 17.2°C | 15.3°C | 25.5°C | 12.9°C | 71 mm | 73% | 5.4 m/s | 4.8 |
| 2011 | 17.9°C | 16.2°C | 14.6°C | 26.2°C | 12.7°C | 55 mm | 78% | 4.9 m/s | 4.3 |
| 2010 | 19.7°C | 17.7°C | 15.8°C | 24.8°C | 13.8°C | 43 mm | 77% | 4.5 m/s | 4.4 |
| 2009 | 18.5°C | 16.6°C | 14.7°C | 25.3°C | 13.1°C | 49 mm | 76% | 5 m/s | 4.6 |
| 2008 | 20.1°C | 17.6°C | 15.1°C | 29.8°C | 12.8°C | 45 mm | 72% | 4.7 m/s | 4.9 |
| 2007 | 19.4°C | 17.4°C | 15.3°C | 26.0°C | 13.1°C | 34 mm | 73% | 5.3 m/s | 5.1 |
| 2006 | 20.2°C | 18.0°C | 15.7°C | 29.3°C | 13.3°C | 23 mm | 74% | 4.6 m/s | 5.1 |
| 2005 | 17.9°C | 16.2°C | 14.5°C | 26.8°C | 12.5°C | 19 mm | 76% | 4.8 m/s | 4.2 |
| 2004 | 18.2°C | 16.3°C | 14.3°C | 28.0°C | 13.0°C | 53 mm | 74% | 4.7 m/s | 4.6 |
| 2003 | 18.0°C | 16.4°C | 14.8°C | 26.2°C | 12.9°C | 47 mm | 78% | 5.2 m/s | 4.5 |
| 2002 | 18.6°C | 16.6°C | 14.6°C | 26.5°C | 13.0°C | 19 mm | 76% | 5 m/s | 4.6 |
| 2001 | 19.4°C | 17.5°C | 15.5°C | 27.9°C | 13.6°C | 67 mm | 72% | 5.2 m/s | 4.6 |
| 2000 | 19.9°C | 17.7°C | 15.4°C | 28.5°C | 12.2°C | 31 mm | 74% | 5 m/s | 4.8 |
| 1999 | 18.3°C | 16.6°C | 14.8°C | 26.2°C | 11.9°C | 53 mm | 75% | 5 m/s | 4.5 |
| 1998 | 19.0°C | 17.0°C | 15.0°C | 30.7°C | 12.8°C | 22 mm | 75% | 5.2 m/s | 4.6 |
| 1997 | 17.8°C | 16.1°C | 14.5°C | 23.6°C | 12.8°C | 36 mm | 76% | 5.3 m/s | 4.6 |
| 1996 | 18.9°C | 16.6°C | 14.4°C | 28.3°C | 12.5°C | 40 mm | 75% | 5.1 m/s | 4.7 |
| 1995 | 18.2°C | 16.4°C | 14.7°C | 26.7°C | 11.0°C | 53 mm | 74% | 5.8 m/s | 4.8 |
| 1994 | 18.7°C | 16.7°C | 14.6°C | 26.0°C | 11.9°C | 7 mm | 72% | 4.2 m/s | 4.6 |
| 1993 | 18.3°C | 16.6°C | 15.0°C | 24.6°C | 13.6°C | 16 mm | 78% | 4.8 m/s | 4.5 |
| 1992 | 19.1°C | 17.2°C | 15.3°C | 27.2°C | 13.2°C | 37 mm | 78% | 4.2 m/s | 4.3 |
| 1991 | 18.1°C | 16.1°C | 14.1°C | 24.3°C | 12.0°C | 57 mm | 73% | 4.9 m/s | 4.8 |
| 1990 | 19.8°C | 17.7°C | 15.6°C | 27.5°C | 13.3°C | 36 mm | 72% | 4.8 m/s | 4.9 |
| 1989 | 19.2°C | 17.7°C | 16.2°C | 29.8°C | 13.8°C | 52 mm | 77% | 5 m/s | 4.1 |
| 1988 | 19.9°C | 17.7°C | 15.5°C | 27.6°C | 13.0°C | 35 mm | 74% | 4.8 m/s | 4.8 |
| 1987 ❄️ | 17.5°C | 15.5°C | 13.5°C | 27.2°C | 11.6°C | 45 mm | 72% | 5.7 m/s | 4.7 |
| 1986 | 20.1°C | 17.5°C | 14.9°C | 32.5°C | 13.2°C | 10 mm | 70% | 4.9 m/s | 4.8 |
| 1985 | 19.7°C | 17.5°C | 15.2°C | 26.2°C | 13.4°C | 49 mm | 76% | 5.1 m/s | 4.4 |
| 1984 | 18.8°C | 16.5°C | 14.2°C | 26.1°C | 11.6°C | 104 mm | 72% | 5.6 m/s | 4.6 |
| 1983 🌧️ | 18.9°C | 17.0°C | 15.1°C | 30.0°C | 11.7°C | 133 mm | 77% | 5.4 m/s | — |
| 1982 | 20.3°C | 17.9°C | 15.4°C | 28.4°C | 13.3°C | 38 mm | 72% | 4.8 m/s | — |
| 1981 | 18.3°C | 16.6°C | 14.8°C | 25.9°C | 13.2°C | 35 mm | 73% | 5.4 m/s | — |
Actual recorded March data for each year, 1981–2025 — sourced from NASA POWER.
The average high in March is around 19.1°C with lows near 15.1°C (mean 17.1°C), based on 45 years of NASA POWER data.
March averages 42 mm of rainfall in Portland, one of the drier months. The wettest on record was 133 mm in 1983.
The hottest March reached 32.5°C in 1986. The coldest dipped to 11°C in 1995.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average March temperatures have risen by about 0.3°C — but days and nights have moved in opposite directions. Overnight lows rose from 14.9°C to 15.7°C while daytime highs eased from 19.2°C to 19.1°C, narrowing the gap between day and night.
March is one of the warmer months of the year in Portland and one of the drier months, so plan for around 19.1°C daytime highs and 15.1°C at night.
Not quite — March is the 10th coolest month in Portland, averaging 17.1°C.
For March in Portland, pack light layers you can adjust through the day, with typical highs of 19.1°C and lows of 15.1°C.
Relative humidity in March averages 75% — moderately humid.
Average wind speed in March is 5 m/s. The windiest March on record averaged 5.8 m/s (1995).
The wettest March on record was 1983 with 133 mm. On average, March sees 42 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in Portland behaves each March, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for March specifically, along with year-by-year records and how the month has changed over the decades.
