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Climate in Thornbury · ECCC 1991–2020 normals

Few Canadian towns get more snow than Thornbury: about 385 cm a year

In January the night’s low is typically −8.7°C. Winters are mild: January nights here are milder than in 81% of Canadian towns. A year here swings 34°C from midwinter lows to midsummer highs. Heating does most of its work from November to April, in months below 10°C on average.

July afternoons: cooler than 55% of Canadian towns

January nights: milder than 81% of Canadian towns

Rain and snow a year: wetter than 80% of Canadian towns

ECCC publishes no normals for Thornbury itself; the figures are those of Collingwood, 18 km east.

July high

25.3°C

Typical Canadian town 25.5°C

January low

−8.7°C

Typical Canadian town −13.5°C

Rain & snow a year

1,074 mm

Typical Canadian town 883 mm

Snowfall a year

385 cm

Typical Canadian town 141 cm

Frost days

131

a year at 0°C or below

A year in Thornbury at a glance

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

Jan−1°C−9°CColdest nightsSnowiest

Feb−1°C−8°C

Mar4°C−4°C

Apr10°C1°C

May17°C7°C

Jun22°C13°C

Jul25°C16°CWarmest

Aug25°C16°C

Sep21°C12°C

Oct14°C6°C

Nov now8°C1°C

Dec2°C−5°C

What stands out about Thornbury’s climate

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

Snowier than almost every Canadian townAbout 385 cm of snow falls in a year, most of it in January. The snowiest of 854 towns of 2,500+ in Ontario.A narrower year than 82% of Canadian townsFrom January nights to July afternoons, the year spans 34.0°C.Milder than 81% of Canadian townsJanuary nights average −8.7°C, the coldest of the year.

A normal year

What a year in Thornbury feels like

Each season’s and each month’s usual high and low, 1991–2020.

Winter

0°C / −7°C

292 mm, with 276 cm of snow

Spring

10°C / 1°C

232 mm, with 57 cm of snow

Summer

24°C / 15°C

232 mm of rain and snow

Autumn

14°C / 6°C

319 mm, with 52 cm of snow: the wettest season

−15°

−10°

−5°

0°

5°

10°

15°

20°

25°

30°

−1°C−9°C

−1°C−8°C

4°C−4°C

10°C1°C

17°C7°C

22°C13°C

25°C16°C

21°C12°C

14°C6°C

8°C1°C

2°C−5°C

JanFebMarAprMayJunJulAugSepOctNovDec

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

Frost & warm days

About 131 frosts and 111 warm days a year

Frost comes from October to April; in January almost every night freezes. About 10 days a year top 30°C.

131

Frost days a year (0°C or below)

Fewer frosts than 79% of Canadian towns

Days that stay below 0°C

Nights a year below −20°C

111

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 1,074 mm a year

January brings the most rain and snow; March, the least. On about 147 days a year, 1 mm or more falls.

1,074 mm

Rain and snow a year

Wetter than 80% of Canadian towns

764 mm

Of it as rain alone (71%)

111 mm

January, the wettest month

66 mm

March, the driest month

Rain and snow by month

Millimetres

111 mm

JFMAMJJASOND

Rain alone by month

Millimetres

106 mm

JFMAMJJASOND

ECCC’s Collingwood normals leave out precipitation and snow; both come from Wiarton here, 58 km away.

Snow

385 cm of snow in a typical year

From October to April snow is likely; January is the peak, at about 111 cm. The snowiest of 854 towns of 2,500+ in Ontario.

385 cm

Snowfall a year

Snowier than almost every Canadian town

Days a year with 0.2 cm of snow or more

Snowfall by month

Centimetres

111 cm

JFMAMJJASOND

Heating

Heating a home in Thornbury

91% of a year’s heating need falls between October and April. Months averaging under 10°C: November to April.

3,904 heating degree days (below 18°C)a year, 1991–2020

2,224 growing degree days (above 5°C)a year, 1991–2020

Degree days add up how far each day’s mean temperature falls below 18°C over a year. Homes here need less heating than 76% of Canadian towns.

Living here

Living with Thornbury’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

Wind chill falls below −20 on about 18 days a year: cover skin and dress in layers.

Humidex

On some 46 days a year the humidex climbs past 30.

Storms and extremes

A normal year has no blizzard, flood or heat wave in it; Thornbury’s hazards page looks at those.

Flood & hazards →

Weather station

ECCC’s normals location: Collingwood

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

Distance from the town	18 km east
Station altitude	178 m
Completeness	at least 20 years
WMO standard normals	No
Precipitation from	Wiarton, 58 km
Coldest reading, 1991–2020	−29.1°C
Hottest reading, 1991–2020	36.5°C
Average wind	12.1 km/h on average, most often from the west
Next-nearest location	Wiarton, 58 km

Compared with other towns

How Thornbury compares

Compared with 2,611 towns and neighbourhoods of 2,500 or more across Canada; the dots mark the other normals locations in Ontario.

July afternoons25.3°C

ThornburyMedian Canadian town

20°C22°C24°C26°C28°C30°C

Cooler than 55% of Canadian towns

January nights−8.7°C

ThornburyMedian Canadian town

−25°C−20°C−15°C−10°C−5°C

Milder than 81% of Canadian towns

Rain and snow a year1,074 mm

ThornburyMedian Canadian town

05001,0001,5002,000

Wetter than 80% of Canadian towns

Snowfall a year385 cm

ThornburyMedian Canadian town

0100200300400

Snowier than almost every Canadian townThe snowiest of 854 towns of 2,500+ in Ontario

Next door

Nearby towns’ climate

Nearby places read from a different ECCC location (places on Thornbury’s own would show the same figures). The nearest places to Thornbury with figures are 38–50 km away.

Town	July high	January low	Rain & snow
Thornbury Collingwood	25.3°C	−8.7°C	1,074 mm
Chatsworth 38 km · Wiarton	24.3°C 1.0°C cooler	−9.9°C 1.2°C colder	1,074 mm
Dundalk 45 km · Mount Forest	25.1°C about the same	−10.9°C 2.2°C colder	1,035 mm
Mulmur 50 km · Egbert	26.0°C 0.7°C warmer	−11.3°C 2.6°C colder	793 mm

Month by month

Thornbury 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	−1.3°C	−8.7°C	−5.0°C	111 mm	111 cm
February	−0.6°C	−8.4°C	−4.5°C	77 mm	74 cm
March	3.7°C	−4.4°C	−0.3°C	66 mm	38 cm
April	10.1°C	1.2°C	5.6°C	84 mm	18 cm
May	17.2°C	7.2°C	12.2°C	82 mm	1 cm
June	22.4°C	12.7°C	17.6°C	79 mm	0 cm
July	25.3°C	16.2°C	20.8°C	70 mm	0 cm
August	24.9°C	15.7°C	20.3°C	83 mm	0 cm
September	21.4°C	12.0°C	16.7°C	99 mm	0 cm
October	14.3°C	6.3°C	10.3°C	110 mm	5 cm
November	7.6°C	0.8°C	4.2°C	110 mm	48 cm
December	1.6°C	−4.7°C	−1.6°C	104 mm	92 cm
Year	12.2°C	3.8°C	8.0°C	1,074 mm	385 cm

Year to year

Two years in three, January’s average lands within 2.8°C of normal, against the steadier August

Over 1991–2020, March saw both −26.7°C (2003) and 27.0°C (2012), the widest span of any month.

−40°

−30°

−20°

−10°

0°

10°

20°

30°

40°

JanFebMarAprMayJunJulAugSepOctNovDec

Record low to record high, 1991–2020Normal

Sources

Where Thornbury’s numbers come from

Averages over 30 years, not a forecast.

Normals: the 1991–2020 normals from ECCC for Collingwood, its nearest location with complete temperatures.
Other locations: ECCC blanks a month that fails its completeness rule, so the precipitation or snowfall here comes from the next location with all twelve months.
Comparisons: Canadian towns and neighbourhoods of at least 2,500, each placed by its nearest location (city totals and reserves excluded).
Not on this page: hours of sunshine, missing from the 1991–2020 normals, and a height correction: the town has no elevation on file.

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

Questions about Thornbury’s climate

How warm does Thornbury get in summer?

Expect highs near 25.3°C in July, the hottest month on average.

How cold does Thornbury get in winter?

Lows sink to −8.7°C on an average January night.

How much rain and snow does Thornbury get?

1,074 mm a year counting snow as water. The wettest month is January (111 mm); the driest, March (66 mm).

Are these figures for Thornbury itself?

No: Thornbury has no normals location, so the figures come from Collingwood, the nearest with 1991–2020 normals.

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

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).