March is one of the cooler months of the year in Ottawa, with average highs near 1.2°C and lows around -9.1°C (mean -3.9°C). It is one of the drier months, averaging 66 mm of rainfall and 88% relative humidity across the period.
March is one of the cooler months of the year in Ottawa. Across 45 years of records, the warmest March in Ottawa was 2012 — when the month averaged 2.9°C — while the coldest was 1984 at -10.2°C. Typical March days reach 1.2°C with nights near -9.1°C. The long-term trend is warming, about 0.7°C per decade.
March is one of the drier months in Ottawa, averaging 66 mm of rainfall. The wettest March on record was 2008 with 116 mm, while the driest was 1996 at 27 mm.
Relative humidity in Ottawa during March averages 88%. The most humid March was 1993 at 98%, and the least humid was 1996 at 76%.
March receives about 3.6 kWh/m²/day of solar energy in Ottawa. The sunniest March was 2005 at 4.5 kWh/m²/day, and the cloudiest was 2022 at 3.
Average wind speed in Ottawa during March is 1.3 m/s. The windiest Marchs were 2002 and 2021 at 1.5 m/s, while the calmest were 1993, 1994 and 2003, among others at 1.1 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | -5.0°C | -4.8°C | -3.9°C | -3.6°C | -1.3°C | +3.7°C |
| Avg High | 0.1°C | 0.2°C | 1.3°C | 1.5°C | 4.1°C | +4°C |
| Avg Low | -10.0°C | -9.8°C | -9.2°C | -8.8°C | -6.7°C | +3.3°C |
| Avg Rain | 62 mm | 75 mm | 68 mm | 59 mm | 65 mm | +3 mm |
March temperatures in Ottawa have risen by about 4.1°C between 1981–1985 and 2021–2025.
March has ranged from a record low of -33.3°C (1984) to a record high of 25.3°C (2012).
Rainfall in March is one of the drier months, averaging 66 mm, with a wettest year of 116 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0.8°C per decade while lows rose 0.6°C per decade, widening the gap between day and night.
A quieter season to visit Ottawa
If your dates are flexible, the more temperate months of July and August tend to be the most comfortable for visiting Ottawa. That said, March — with days averaging 1.2°C and nights around -9.1°C (mean -3.9°C) and moderate rainfall (66 mm) — can still be rewarding for travellers who don't mind the cooler conditions, and often means fewer crowds.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 4.5°C | -1.2°C | -6.8°C | 18.4°C | -25.2°C | 78 mm | 82% | 1.4 m/s | 3.3 |
| 2024 | 7.0°C | 1.6°C | -3.8°C | 16.1°C | -14.2°C | 42 mm | 77% | 1.3 m/s | 3.7 |
| 2023 | 1.8°C | -2.7°C | -7.3°C | 7.4°C | -21.6°C | 56 mm | 86% | 1.3 m/s | 3.3 |
| 2022 | 3.0°C | -2.3°C | -7.6°C | 16.5°C | -25.0°C | 63 mm | 84% | 1.3 m/s | 3 |
| 2021 | 4.8°C | -1.6°C | -8.0°C | 19.4°C | -21.9°C | 61 mm | 81% | 1.5 m/s | 4 |
| 2020 | 3.3°C | -1.8°C | -6.9°C | 14.1°C | -22.8°C | 88 mm | 87% | 1.3 m/s | 3.4 |
| 2019 | 0.2°C | -5.0°C | -10.3°C | 9.2°C | -26.2°C | 61 mm | 88% | 1.3 m/s | 3.7 |
| 2018 | 0.9°C | -3.4°C | -7.7°C | 9.4°C | -23.3°C | 51 mm | 88% | 1.4 m/s | 3.6 |
| 2017 | -1.0°C | -5.9°C | -10.8°C | 9.3°C | -23.8°C | 85 mm | 80% | 1.4 m/s | 3.6 |
| 2016 | 1.9°C | -3.1°C | -8.0°C | 12.8°C | -29.6°C | 99 mm | 87% | 1.2 m/s | 3.6 |
| 2015 | -1.7°C | -7.3°C | -12.8°C | 6.1°C | -27.6°C | 31 mm | 90% | 1.3 m/s | 4 |
| 2014 | -4.1°C | -9.9°C | -15.7°C | 3.6°C | -26.5°C | 53 mm | 93% | 1.2 m/s | 4 |
| 2013 | 2.6°C | -1.9°C | -6.3°C | 12.3°C | -16.3°C | 30 mm | 83% | 1.3 m/s | 3.3 |
| 2012 🔥 | 8.6°C | 2.9°C | -2.9°C | 25.3°C | -20.6°C | 53 mm | 81% | 1.3 m/s | 3.5 |
| 2011 | 0.4°C | -4.4°C | -9.3°C | 9.3°C | -21.7°C | 94 mm | 87% | 1.3 m/s | 3.7 |
| 2010 | 7.1°C | 1.6°C | -3.9°C | 16.2°C | -10.9°C | 36 mm | 81% | 1.3 m/s | 4 |
| 2009 | 3.3°C | -2.2°C | -7.7°C | 13.9°C | -21.7°C | 48 mm | 81% | 1.3 m/s | 3.9 |
| 2008 🌧️ | -2.7°C | -8.0°C | -13.3°C | 4.0°C | -22.7°C | 116 mm | 97% | 1.3 m/s | 3.5 |
| 2007 | 0.6°C | -4.8°C | -10.3°C | 12.3°C | -31.3°C | 74 mm | 88% | 1.4 m/s | 3.4 |
| 2006 | 0.8°C | -4.1°C | -9.0°C | 20.5°C | -26.2°C | 42 mm | 89% | 1.3 m/s | 3.8 |
| 2005 | 0.7°C | -4.8°C | -10.3°C | 16.9°C | -19.6°C | 36 mm | 88% | 1.3 m/s | 4.5 |
| 2004 | 4.1°C | -1.0°C | -6.1°C | 17.3°C | -15.5°C | 71 mm | 85% | 1.3 m/s | 3.3 |
| 2003 | -0.5°C | -6.2°C | -11.8°C | 14.0°C | -30.7°C | 83 mm | 92% | 1.1 m/s | 3.4 |
| 2002 | 2.2°C | -3.1°C | -8.3°C | 15.4°C | -18.8°C | 87 mm | 81% | 1.5 m/s | 3.2 |
| 2001 | -2.2°C | -6.2°C | -10.3°C | 1.0°C | -23.7°C | 55 mm | 96% | 1.2 m/s | 3.5 |
| 2000 | 6.5°C | 1.0°C | -4.5°C | 16.6°C | -14.3°C | 71 mm | 79% | 1.3 m/s | 3.3 |
| 1999 | -0.5°C | -5.3°C | -10.2°C | 17.7°C | -24.7°C | 113 mm | 92% | 1.4 m/s | 4.1 |
| 1998 | 2.3°C | -2.4°C | -7.1°C | 22.1°C | -22.9°C | 104 mm | 93% | 1.2 m/s | 3.3 |
| 1997 | -2.5°C | -7.9°C | -13.4°C | 8.4°C | -27.0°C | 83 mm | 97% | 1.3 m/s | 3.8 |
| 1996 | 1.7°C | -3.5°C | -8.7°C | 12.9°C | -18.1°C | 27 mm | 76% | 1.3 m/s | 4 |
| 1995 | 5.5°C | -0.3°C | -6.2°C | 18.2°C | -20.8°C | 42 mm | 85% | 1.2 m/s | 3.4 |
| 1994 | -0.8°C | -5.4°C | -10.1°C | 6.0°C | -21.5°C | 66 mm | 95% | 1.1 m/s | 3.6 |
| 1993 | -2.5°C | -7.3°C | -12.0°C | 1.8°C | -29.8°C | 76 mm | 98% | 1.1 m/s | 3.6 |
| 1992 | -3.9°C | -8.5°C | -13.0°C | 3.2°C | -29.6°C | 99 mm | 97% | 1.1 m/s | 4.1 |
| 1991 | 1.2°C | -3.4°C | -7.9°C | 11.4°C | -21.8°C | 95 mm | 89% | 1.3 m/s | 3.6 |
| 1990 | 1.8°C | -3.7°C | -9.2°C | 19.6°C | -28.3°C | 42 mm | 88% | 1.2 m/s | 3.5 |
| 1989 | -1.2°C | -7.2°C | -13.1°C | 18.9°C | -32.3°C | 79 mm | 91% | 1.2 m/s | 3.4 |
| 1988 | 0.8°C | -5.1°C | -11.0°C | 17.8°C | -22.7°C | 32 mm | 85% | 1.3 m/s | 3.6 |
| 1987 | 1.6°C | -3.1°C | -7.7°C | 14.3°C | -26.4°C | 69 mm | 95% | 1.1 m/s | 3.2 |
| 1986 | 2.3°C | -3.1°C | -8.5°C | 18.9°C | -23.4°C | 71 mm | 89% | 1.3 m/s | 3.7 |
| 1985 | -1.4°C | -6.2°C | -11.0°C | 7.9°C | -21.5°C | 86 mm | 93% | 1.4 m/s | 3.5 |
| 1984 ❄️ | -5.0°C | -10.2°C | -15.4°C | 2.5°C | -33.3°C | 37 mm | 96% | 1.3 m/s | 3.5 |
| 1983 | 2.7°C | -2.1°C | -6.8°C | 11.7°C | -18.7°C | 62 mm | 85% | 1.4 m/s | — |
| 1982 | -2.2°C | -6.7°C | -11.2°C | 13.5°C | -24.8°C | 76 mm | 97% | 1.3 m/s | — |
| 1981 | 3.1°C | -1.2°C | -5.6°C | 16.9°C | -13.1°C | 43 mm | 82% | 1.2 m/s | — |
Actual recorded March data for each year, 1981–2025 — sourced from NASA POWER.
The average high in March is around 1.2°C with lows near -9.1°C (mean -3.9°C), based on 45 years of NASA POWER data.
March averages 66 mm of rainfall in Ottawa, one of the drier months. The wettest on record was 116 mm in 2008.
The hottest March reached 25.3°C in 2012. The coldest dipped to -33.3°C in 1984.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average March temperatures have risen by about 4.1°C. Daytime highs moved from -0.6°C to 4.2°C and overnight lows from -10°C to -6.7°C over the same span.
March is one of the cooler months of the year in Ottawa and one of the drier months, so plan for around 1.2°C daytime highs and -9.1°C at night.
Not quite — March is the 4th coolest month in Ottawa, averaging -3.9°C.
For March in Ottawa, pack warm layers and a jacket for chilly mornings, with typical highs of 1.2°C and lows of -9.1°C. Bring an umbrella or light rain jacket too.
Relative humidity in March averages 88% — quite humid.
Average wind speed in March is 1.3 m/s. The windiest March on record averaged 1.5 m/s (2002).
The wettest March on record was 2008 with 116 mm. On average, March sees 66 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 Ottawa 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.
