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Ottawa, Canada All-Time Weather Extremes

The most extreme temperature, precipitation, and snowfall ever recorded in Ottawa, from NOAA GHCN daily weather observations.

Station: OTTAWA CDA
All-time weather extremes for Ottawa, Canada, from NOAA daily observations at OTTAWA CDA
Temperature
Record High100°F (38°C)July 4, 1913 and July 30, 1916 and August 1, 1917
Record Low-38°F (-39°C)December 29, 1933
Lowest High-25°F (-32°C)December 29, 1933
Highest Low76.6°F (25°C)August 9, 2001
Highest Mean87.8°F (31°C)August 9, 2001
Lowest Mean-31.5°F (-35°C)December 29, 1933
Precipitation
Max in One Calendar Day4.28" (108.6 mm)September 9, 2004
Max in One Month9.85" (250.2 mm)July 1899
Least in One Month0.10" (2.6 mm)February 1978
Max in One Year46.56" (1182.7 mm)2017
Least in One Year24.33" (618.0 mm)1931
Snowfall
Max in One Calendar Day22.0" (55.9 cm)January 29, 1894
Max in One Month54.3" (137.8 cm)February 1971
Max in One Season152.7" (387.8 cm)1970-71
Max in One Year140.5" (356.9 cm)1971
Earliest Snow1.7" (4.4 cm)October 8, 1979
Earliest Measurable Snow1.7" (4.4 cm)October 8, 1979
Latest Snow0.2" (0.4 cm)May 26, 1994
Latest Measurable Snow0.2" (0.4 cm)May 26, 1994
Period of Record
TemperatureNovember 1, 1889 – April 1, 2024
PrecipitationNovember 1, 1889 – April 1, 2024
SnowfallNovember 1, 1889 – April 1, 2024

Note: Records compiled from NOAA GHCN-Daily observations at OTTAWA CDA (3 mi from Ottawa, Canada). Quality-flagged readings are excluded. Monthly and annual totals require substantially complete reporting for “least” records.

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Ottawa, Canada all-time weather extremes table — record high 100°F on July 4, 1913, record low -38°F on December 29, 1933, with precipitation and snowfall records from NOAA data

Frequently Asked Questions

What is the hottest temperature ever recorded in Ottawa, Canada?

The all-time record high in Ottawa, Canada is 100°F (38°C), set on July 4, 1913 and July 30, 1916 and August 1, 1917.

What is the coldest temperature ever recorded in Ottawa, Canada?

The all-time record low in Ottawa, Canada is -38°F (-39°C), set on December 29, 1933.

What is the most rain Ottawa, Canada has ever had in one day?

The most precipitation recorded in one calendar day near Ottawa, Canada is 4.28 inches, on September 9, 2004.

What is the biggest snowfall ever recorded in Ottawa, Canada?

The most snow recorded in one calendar day near Ottawa, Canada is 22.0 inches, on January 29, 1894.

Weather Extremes in Other Canada Cities

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