Rue principale à l' Assomption . - [1930]

Photo: Unknown Unknown · Public domain

Climate in L'Assomption · ECCC 1991–2020 normals

Precipitation in L'Assomption tops that of 82% of Canadian towns: 1,109 mm a year

January mornings start at about −16.0°C. August is the wettest month, February the driest. Winter nights are cold: in January they are colder than in 75% of Canadian towns. The heating season runs October to April: each of those months averages under 10°C.

July afternoons: warmer than 70% of Canadian towns

January nights: colder than 75% of Canadian towns

Rain and snow a year: wetter than 82% of Canadian towns

1991–2020 normals from ECCC’s L'Assomption station, 4.6 km south.

July high

26.6°C

Typical Canadian town 25.5°C

January low

−16.0°C

Typical Canadian town −13.5°C

Rain & snow a year

1,109 mm

Typical Canadian town 883 mm

Snowfall a year

202 cm

Typical Canadian town 141 cm

Frost days

161

a year at 0°C or below

A year in L'Assomption at a glance

Each month’s typical high and low, in °C.

Jan−6°C−16°CColdest nights

Feb−4°C−15°C

Mar2°C−8°C

Apr11°C0°C

May19°C7°C

Jun24°C12°C

Jul27°C15°CWarmest

Aug26°C14°CWettest

Sep21°C9°C

Oct13°C3°C

Nov now5°C−3°C

Dec−2°C−10°CSnowiest

What stands out about L'Assomption’s climate

Compared with Canadian towns, with its place among towns of 2,500+ in Quebec beside it.

A wider year than 82% of Canadian townsFrom January nights to July afternoons, the year spans 42.6°C.Wetter than 82% of Canadian townsAbout 1,109 mm of rain and melted snow a year; August is the wettest month and February the driest.Colder than 75% of Canadian townsJanuary nights average −16.0°C, the coldest of the year.

A normal year

What a year in L'Assomption feels like

Seasons and months as ECCC’s 1991–2020 normals give them: a typical day’s high and low.

Winter

−4°C / −14°C

227 mm, with 137 cm of snow

Spring

11°C / 0°C

265 mm, with 52 cm of snow

Summer

25°C / 14°C

322 mm of rain and snow, the wettest season

Autumn

13°C / 3°C

295 mm, with 14 cm of snow

−20°

−10°

0°

10°

20°

30°

40°

−6°C−16°C

−4°C−15°C

2°C−8°C

11°C0°C

19°C7°C

24°C12°C

27°C15°C

26°C14°C

21°C9°C

13°C3°C

5°C−3°C

−2°C−10°C

JanFebMarAprMayJunJulAugSepOctNovDec

Best months to be outsideJunJulAugSepHighs of 17–27°C and nights of 8°C or more

Frost & warm days

About 161 frosts and 119 warm days a year

From October to May frost is routine, and in January it comes on almost every night. On about 24 nights a year the air falls below −20°C.

161

Frost days a year (0°C or below)

More frosts than 52% of Canadian towns

Days that stay below 0°C

Nights a year below −20°C

119

Days a year above 20°C

Days a year above 30°C

Frost days by month

Average days at 0°C or below

JFMAMJJASOND

Days above 20°C by month

Average days

JFMAMJJASOND

Rain & snow

Rain and melted snow: about 1,109 mm a year

On about 145 days a year, 1 mm or more falls.

1,109 mm

Rain and snow a year

Wetter than 82% of Canadian towns

899 mm

Of it as rain alone (81%)

114 mm

August, the wettest month

61 mm

February, the driest month

Rain and snow by month

Millimetres

114 mm

JFMAMJJASOND

Rain alone by month

Millimetres

114 mm

JFMAMJJASOND

ECCC’s L'Assomption normals leave out precipitation and snow; both come from Fleury here, 33 km away.

Snow

Snowfall: about 202 cm in a normal year

Expect snow from October to April, with about 49 cm in December, the snowiest month.

202 cm

Snowfall a year

Snowier than 72% of Canadian towns

Days a year with 0.2 cm of snow or more

Snowfall by month

Centimetres

49 cm

JFMAMJJASOND

Heating

Heating a home in L'Assomption

93% of a year’s heating need falls between October and April. Months averaging under 10°C: October to April.

4,592 heating degree days (below 18°C)a year, 1991–2020

2,093 growing degree days (above 5°C)a year, 1991–2020

Measured against 18°C: each day’s shortfall in mean temperature, added over twelve months.

Living here

Living with L'Assomption’s climate

The averages read for the garden, the outdoors and the coldest and hottest days.

Get outside

Plan time outside for Jun, Jul, Aug and Sep: highs of 17–27°C and nights no colder than 8°C.

Parks & trails →

Wind chill

Roughly 44 days a year feel colder than −20 in the wind.

Humidex

Humid heat, a humidex over 30, comes on about 49 days a year.

Storms and extremes

Bad-weather days, from blizzards to floods, get their own page for L'Assomption: the hazards page.

Flood & hazards →

Weather station

ECCC’s normals location: L'Assomption

The page’s figures are ECCC’s 1991–2020 normals for L'Assomption, one of its 450 normals locations.

Distance from the town	4.6 km south
Station altitude	21 m
Completeness	meets the WMO “3 and 5” rule
WMO standard normals	No
Precipitation from	Fleury, 33 km
Coldest reading, 1991–2020	−40.0°C
Hottest reading, 1991–2020	36.2°C
Average wind	10.0 km/h on average, most often from the south-west
Next-nearest location	Fleury, 33 km

Compared with other towns

How L'Assomption compares

Against the 2,611 Canadian towns and neighbourhoods of 2,500 or more, each read from its own normals location; the dots are the other locations those towns use in Quebec.

July afternoons26.6°C

L'AssomptionMedian Canadian town

18°C20°C22°C24°C26°C28°C

Warmer than 70% of Canadian towns

January nights−16.0°C

L'AssomptionMedian Canadian town

−30°C−25°C−20°C−15°C−10°C−5°C

Colder than 75% of Canadian towns

Rain and snow a year1,109 mm

L'AssomptionMedian Canadian town

05001,0001,5002,000

Wetter than 82% of Canadian towns

Snowfall a year202 cm

L'AssomptionMedian Canadian town

100200300400

Snowier than 72% of Canadian towns

Next door

Nearby towns’ climate

Nearby places read from a different ECCC location (places on L'Assomption’s own would show the same figures). No closer place has figures: this one lies 20 km from L'Assomption.

Town	July high	January low	Rain & snow
L'Assomption	26.6°C	−16.0°C	1,109 mm
Saint-Antoine-sur-Richelieu 20 km · Fleury	26.0°C 0.6°C cooler	−14.8°C 1.2°C milder	1,109 mm

Month by month

L'Assomption weather by month

Month by month, 1991–2020: the usual high, low and mean, the rain and snow, and the snowfall.

Month	High	Low	Mean	Rain & snow	Snow
January	−5.9°C	−16.0°C	−10.9°C	81 mm	45 cm
February	−4.0°C	−14.8°C	−9.4°C	61 mm	43 cm
March	1.8°C	−8.3°C	−3.2°C	71 mm	38 cm
April	10.8°C	0.1°C	5.5°C	96 mm	13 cm
May	19.2°C	7.2°C	13.2°C	98 mm	under 1 cm
June	24.3°C	12.4°C	18.4°C	102 mm	0 cm
July	26.6°C	14.8°C	20.7°C	106 mm	0 cm
August	25.5°C	13.7°C	19.6°C	114 mm	0 cm
September	21.1°C	9.2°C	15.2°C	97 mm	0 cm
October	13.0°C	3.2°C	8.1°C	108 mm	2 cm
November	5.4°C	−2.7°C	1.3°C	90 mm	12 cm
December	−1.9°C	−10.2°C	−6.1°C	85 mm	49 cm
Year	11.3°C	0.7°C	6.0°C	1,109 mm	202 cm

Year to year

The month with the widest range: March, −29.5°C to 26.0°C

Bars run from each month’s record low to its record high over 1991–2020; January is the month whose average wanders most from year to year (±3.1°C around −10.9°C), June the one that wanders least (±1.0°C).

−50°

−40°

−30°

−20°

−10°

0°

10°

20°

30°

40°

JanFebMarAprMayJunJulAugSepOctNovDec

Record low to record high, 1991–2020Normal

Sources

Where L'Assomption’s numbers come from

Averages over 30 years, not a forecast.

Normals: ECCC’s 1991–2020 Canadian Climate Normals for L'Assomption, the nearest location with a full year of temperatures.
Other locations: where a location publishes no full year of precipitation or snowfall, the nearest one that does supplies it, named beside those figures.
Comparisons: Canada’s towns and neighbourhoods of 2,500+ (no city totals, no reserves), each through its own nearest location.
Not on this page: sunshine (no 1991–2020 normals exist for it) and any altitude adjustment, since there is no elevation for the town itself.

Canadian Climate Normals 1991–2020 · ECCC Data Services End-use Licence. Data Source: Environment and Climate Change Canada

Questions about L'Assomption’s climate

How warm does L'Assomption get in summer?

The warmest month is July, when afternoons average 26.6°C.

How cold does L'Assomption get in winter?

January nights average −16.0°C, the coldest of the year.

How much rain and snow does L'Assomption get?

Rain and snow, with snow counted as water, total 1,109 mm a year; August leads with 114 mm and February trails with 61 mm.

Are these figures for L'Assomption itself?

They are: the normals station that gives them stands in L'Assomption.

Data Source: Environment and Climate Change Canada · ECCC Data Services End-use Licence Today’s forecast for L'Assomption →

Adapted from Statistics Canada (Census of Population 2021, population estimates 2025, 2021 census boundaries) under the Statistics Canada Open Licence; this does not constitute an endorsement by Statistics Canada. Neighbourhood names in some cities © OpenStreetMap contributors (ODbL).