Weather and climate in Montreal (Canada)

In Montreal, the largest city of Québec, located in southeastern Canada, the climate is continental, with very cold winters and warm summers. Although the city is located on the 45th parallel, ie halfway between the Pole and the Equator, it's freezing in winter because the North American land mass cools down a lot, and outbreaks of polar air masses are frequent.
Here are the average temperatures at the Trudeau (Dorval) airport.

Precipitation amounts to about 1,000 millimeters (40 inches) per year and is well distributed over the seasons: in fact, weather fronts pass over the city in all months, and are due to the continual clash between warm and cold air masses. In the only season when this clash is less frequent, ie in summer, thunderstorms can develop in the afternoon, adding more rain, so much so that summer is as rainy as autumn, at least in quantity.
Here is the average precipitation.

During the long winter months, from mid-November to early April, precipitation mostly occurs as snow. Snow normally covers the ground from late November to mid-March. In Montreal, more than two meters (6 foot 5") of snow fall per year. Occasionally, a snowfall can be seen already in October, and in spring, still in early May. In the winter of 2007/2008, a total of 436 cm (14.3 ft) of snow fell.

Winter in Montreal runs from mid-November to mid-March and is very cold, in fact, the average temperature, about -9 °C (16 °F) in January, is similar to that of Moscow, Russia. However, at least, the days here are not as short as in Nordic countries because, as mentioned, the latitude is not very high.
Waves of freezing cold are accompanied by the Blizzard, the north wind blowing in gusts, or by the Barber, the cold and wet wind able to freeze beard and hair, which blows from the north-east, ie from the Gulf of St. Lawrence.
Given the constant weather instability, the temperature may exceed freezing (0 °C or 32 °F) even in winter, and in these cases, snow can melt and it can rain. On the other hand, intense cold waves, with lows around -25/-30 °C (-13/-22 °F), occur practically every year. The coldest record is -37.8 °C (-36 °F) and was set in January 1957.
Snowfalls are frequent, in fact, it snows for several days per month; occasionally, there can be real snow storms, like that of March 4, 1971, with 43 cm (17 in) of snow in 24 hours, or that of December 27, 2012, with 45 cm (17.7 in) in 24 hours.

Spring, from mid-March to May, is an unstable season, characterized by temperature swings. It is initially cold in March, with snowfalls and frosts still frequent, then it gradually advances, between the first warm days and the return of cold weather, and it's normally cold still in April, while it becomes mild by May, when also thunderstorms begin to develop in the afternoon.

Summer, from June to August, is quite warm, and on hot days, it is also sultry because of the contribution given by the rivers, Saint Lawrence and Ottawa, which widen near the city, creating lakes that provide additional moisture. It is said, a little ironically, that there are only two seasons in Montreal: the winter and the month of July: obviously, this is an exaggeration, but there is some truth, in the sense that July stands out as the warmest and sunniest month; August is not really so different, but it's already a bit cooler and less sunny. However, in summer, there is a moderate amount of cool and cloudy days, while on fine days, thunderstorms can erupt in the afternoon.
There can be periods with hot and humid weather, with lows around 20/22 °C (68/72 °F) and highs around 32/33 °C (90/91 °F), which typically only last a few days. More rarely, it can even get hotter, as happened in July 2020 and August 2001, when the temperature reached 36 °C (97 °F). The record was equaled in late May 2020, during an early heatwave.

Autumn, from September to mid-November, is initially pleasant, in fact, with several sunny days, with temperatures exceeding 25 °C (77 °F): this kind of weather, called Indian summer, usually occurs in September, but sometimes also in the first half of October. As the weeks pass, however, the temperature decreases rapidly, bad weather becomes more frequent, and the first cold days occur.



The amount of sunshine in Montréal is good in late spring and summer; in the other months, it is not high, and it is quite scarce in winter, when the sun is very rarely seen. On average there are 2,055 hours of sunshine per year. Here are the average sunshine hours per day.

Best Time

The best time to visit Montréal is from mid-May to late September. In midsummer, especially in July and early August, there can be hot and muggy days, so, this period can be excluded if you cannot stand the heat. In May and early June, it can still be a bit cold. However, you always have to take into account the possibility of rain and changes in temperature.

Montreal - Weather by month

Based on the period 1991-2020

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January, the coldest month of the year, is generally a freezing cold month. The average temperature is of -8.9 °C (16 °F), with a minimum of -13.6 °C (7.5 °F) and a maximum of -4.2 °C (24.4 °F).
On the coldest nights of the month, the temperature usually drops to around -25 °C (-13.5 °F). However, it dropped to -31.8 °C (-25.2 °F) in January 1994.
On the warmest days of the month, the temperature usually reaches around 7 °C (44.5 °F). However, it reached 13.1 °C (55.6 °F) in January 1996.
Precipitation amounts to 75 mm (3 in), distributed over 17 days.
The day lasts on average 9 hours and 10 minutes.
There are on average 3.5 hours of sunshine per day. So, the sun shines 36% of the time.
The average humidity is 71%. Hence, the air is normally humid.
The average wind speed is 17 kph (10 mph).

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February is generally a freezing cold month. The average temperature is of -7.4 °C (19 °F), with a minimum of -12.3 °C (9.9 °F) and a maximum of -2.5 °C (27.5 °F).
On the coldest nights of the month, the temperature usually drops to around -22.5 °C (-8.5 °F). However, it dropped to -30.3 °C (-22.5 °F) in February 1993.
On the warmest days of the month, the temperature usually reaches around 6.5 °C (44 °F). However, it reached 15 °C (59 °F) in February 2017.
Precipitation amounts to 65 mm (2.6 in), distributed over 14 days.
The day lasts on average 10 hours and 25 minutes.
There are on average 4.5 hours of sunshine per day. So, the sun shines 44% of the time.
The average humidity is 68%.
The average wind speed is 17 kph (10 mph).

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March is generally a very cold month. The average temperature is of -1.8 °C (29 °F), with a minimum of -6.7 °C (19.9 °F) and a maximum of 3.2 °C (37.8 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -18 °C (-0.5 °F). However, it dropped to -26.9 °C (-16.4 °F) in March 1992.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 13.5 °C (56 °F). However, it reached 26 °C (78.8 °F) in March 2012.
Precipitation amounts to 70 mm (2.8 in), distributed over 14 days.
The day lasts on average 12 hours and 0 minutes.
There are on average 5.5 hours of sunshine per day. So, the sun shines 44% of the time.
The average humidity is 64%.
The average wind speed is 16 kph (10 mph).

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April is generally a quite cold month. The average temperature is of 6.4 °C (43 °F), with a minimum of 0.8 °C (33.4 °F) and a maximum of 11.9 °C (53.4 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -6.5 °C (20.5 °F). However, it dropped to -14.5 °C (5.9 °F) in April 1995.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 23 °C (73.5 °F). However, it reached 29.4 °C (84.9 °F) in April 2009.
Precipitation amounts to 80 mm (3.1 in), distributed over 13 days.
The day lasts on average 13 hours and 35 minutes.
There are on average 6 hours of sunshine per day. So, the sun shines 44% of the time.
The average humidity is 59%.
The average wind speed is 17 kph (11 mph).

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May is generally a mild month. The average temperature is of 14.0 °C (57 °F), with a minimum of 7.8 °C (46 °F) and a maximum of 20.1 °C (68.2 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 1 °C (34 °F). However, it dropped to -1.9 °C (28.6 °F) in May 1997.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 29 °C (84.5 °F). However, it reached 36 °C (96.8 °F) in May 2020.
Precipitation amounts to 80 mm (3.1 in), distributed over 14 days.
The day lasts on average 15 hours and 0 minutes. So the days are long.
There are on average 7.5 hours of sunshine per day. So, the sun shines 49% of the time.
The average humidity is 60%.
The average wind speed is 15 kph (10 mph).

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June is generally a warm month. The average temperature is of 19.2 °C (67 °F), with a minimum of 13.5 °C (56.3 °F) and a maximum of 24.9 °C (76.8 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 7 °C (44 °F). However, it dropped to 2.8 °C (37 °F) in June 2020.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 31.5 °C (88.5 °F). However, it reached 35 °C (95 °F) in June 2020.
Precipitation amounts to 85 mm (3.3 in), distributed over 13 days.
The day lasts on average 15 hours and 35 minutes. So the days are long. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
There are on average 8 hours of sunshine per day. So, the sun shines 51% of the time.
The average humidity is 65%.
The average wind speed is 14 kph (9 mph).

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July, the warmest month of the year, is generally a warm month. The average temperature is of 21.8 °C (71 °F), with a minimum of 16.4 °C (61.5 °F) and a maximum of 27.2 °C (81 °F).
On the coldest nights of the month, the temperature usually drops to around 11.5 °C (52.5 °F). However, it dropped to 7.1 °C (44.8 °F) in July 1992.
On the warmest days of the month, the temperature usually reaches around 32.5 °C (90.5 °F). However, it reached 36 °C (96.8 °F) in July 2020.
Precipitation amounts to 90 mm (3.5 in), distributed over 12 days.
The day lasts on average 15 hours and 10 minutes. So the days are long.
There are on average 9 hours of sunshine per day. So, the sun shines 58% of the time.
The average humidity is 67%.
The average wind speed is 14 kph (8 mph).

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August is generally a warm month. The average temperature is of 20.8 °C (70 °F), with a minimum of 15.4 °C (59.7 °F) and a maximum of 26.3 °C (79.3 °F).
On the coldest nights of the month, the temperature usually drops to around 9.5 °C (48.5 °F). However, it dropped to 6.2 °C (43.2 °F) in August 1993.
On the warmest days of the month, the temperature usually reaches around 31.5 °C (89 °F). However, it reached 36.2 °C (97.2 °F) in August 2001.
Precipitation amounts to 95 mm (3.7 in), distributed over 12 days.
The day lasts on average 14 hours and 0 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 57% of the time.
The average humidity is 69%.
The average wind speed is 13 kph (8 mph).

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September is generally a very mild month. The average temperature is of 16.4 °C (62 °F), with a minimum of 10.9 °C (51.6 °F) and a maximum of 22 °C (71.6 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 3.5 °C (38 °F). However, it dropped to -1.8 °C (28.8 °F) in September 1991.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 29.5 °C (85 °F). However, it reached 33.5 °C (92.3 °F) in September 1999.
Precipitation amounts to 85 mm (3.3 in), distributed over 11 days.
The day lasts on average 12 hours and 30 minutes.
There are on average 6 hours of sunshine per day. So, the sun shines 49% of the time.
The average humidity is 71%. Hence, the air is normally humid.
The average wind speed is 13 kph (8 mph).

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October is generally a mild month. The average temperature is of 9.4 °C (49 °F), with a minimum of 4.6 °C (40.3 °F) and a maximum of 14.2 °C (57.6 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -3 °C (26.5 °F). However, it dropped to -6 °C (21.2 °F) in October 2020.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 23.5 °C (74 °F). However, it reached 27 °C (80.6 °F) in October 2018.
Precipitation amounts to 90 mm (3.5 in), distributed over 13 days.
The day lasts on average 10 hours and 55 minutes.
There are on average 4.5 hours of sunshine per day. So, the sun shines 42% of the time.
The average humidity is 72%. Hence, the air is normally humid.
The average wind speed is 15 kph (9 mph).

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November is generally a cold month. The average temperature is of 2.4 °C (36 °F), with a minimum of -1.8 °C (28.8 °F) and a maximum of 6.7 °C (44.1 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -10 °C (14 °F). However, it dropped to -18 °C (-0.4 °F) in November 2018.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 17 °C (62.5 °F). However, it reached 22.4 °C (72.3 °F) in November 2020.
Precipitation amounts to 95 mm (3.7 in), distributed over 15 days.
The day lasts on average 9 hours and 30 minutes.
There are on average 3 hours of sunshine per day. So, the sun shines 29% of the time.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is 16 kph (10 mph).

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December is generally a very cold month. The average temperature is of -4.4 °C (24 °F), with a minimum of -8.5 °C (16.7 °F) and a maximum of -0.3 °C (31.5 °F).
On the coldest nights of the month, the temperature usually drops to around -20 °C (-4 °F). However, it dropped to -31 °C (-23.8 °F) in December 1993.
On the warmest days of the month, the temperature usually reaches around 10 °C (50.5 °F). However, it reached 18 °C (64.4 °F) in December 2001.
Precipitation amounts to 85 mm (3.3 in), distributed over 16 days.
The day lasts on average 8 hours and 50 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
There are on average 2.5 hours of sunshine per day. So, the sun shines 31% of the time.
The average humidity is 76%. Hence, the air is normally humid.
The average wind speed is 16 kph (10 mph).