Photo: The original uploader was Cherkowski at Wikipedia . · CC BY 2.5Few Canadian towns have colder winter nights than Cornwallis
On a normal July day the thermometer tops out near 24.9°C. Its yearly rain and snow fall short of 76% of Canadian towns. Winter and summer sit 47°C apart. For walks and days out, the stretch from June to August brings highs of 23–25°C.
Borrowed figures: Cornwallis has no normals station, so these come from Brandon, 20 km north-west.
A year in Cornwallis at a glance
Each month’s typical high and low, in °C.
What stands out about Cornwallis’s climate
Compared with Canadian towns, with its place among towns of 2,500+ in Manitoba beside it.
What a year in Cornwallis feels like
Each season’s and each month’s usual high and low, 1991–2020.
About 205 frosts and 103 warm days a year
Frost comes from September to May; in January almost every night freezes. On about 53 nights a year the air falls below −20°C.
Frost days by month
Average days at 0°C or below
Days above 20°C by month
Average days
Rain and melted snow: about 489 mm a year
The most falls in June, the least in February. About 73 days a year bring 1 mm or more.
Rain and snow by month
Millimetres
Rain alone by month
Millimetres
About 128 cm of snow a year
Snow falls from October to May, most of all in December (about 29 cm).
Snowfall by month
Centimetres
Snow on the ground by month
Centimetres at month’s end
Heating a home in Cornwallis
90% of a year’s heating need falls between October and April. Months averaging under 10°C: October to April.
Every day colder than 18°C on average adds its gap in degrees to the year’s heating total. That means homes here need more heating than 97% of Canadian towns.
Living with Cornwallis’s climate
Gardening, time outside, winter cold and summer heat, from the 1991–2020 normals.
Wait until about 18 May to plant out; frost tends to come back around 18 September, about 122 days later.
Highs of 17–27°C with nights of 8°C or more come in Jun, Jul and Aug.
Parks & trails →Wind chill falls below −20 on about 87 days a year: cover skin and dress in layers.
Muggy heat with a humidex over 30 arrives on about 31 days a year.
Extremes don’t show in averages: floods, wildfire smoke and ice storms are on Cornwallis’s hazards page.
Flood & hazards →ECCC’s normals location: Brandon
Brandon is a composite: ECCC joins 2 stations’ readings to make its 1991–2020 normals.
| Distance from the town | 20 km north-west |
| Station altitude | 409 m |
| Completeness | meets the WMO “3 and 5” rule |
| WMO standard normals | No |
| Coldest reading, 1991–2020 | −43.2°C |
| Hottest reading, 1991–2020 | 37.9°C |
| Average wind | 15.2 km/h on average, most often from the west |
| Next-nearest location | Cypress River, 54 km |
How Cornwallis compares
Placed among 2,611 Canadian towns and neighbourhoods of 2,500+, each on its nearest normals location; each dot is another location used in Manitoba.
Nearby towns’ climate
Places around Cornwallis whose figures come from another normals location. Cornwallis has no close neighbour with figures; the nearest is 26 km away.
| Town | July high | January low | Rain & snow |
|---|---|---|---|
| Cornwallis Brandon | 24.9°C | −21.9°C | 489 mm |
| Carberry 26 km · Cypress River | 25.9°C 1.0°C warmer | −20.1°C 1.8°C milder | 517 mm |
Cornwallis weather by month
Each month’s normals, 1991–2020: high, low, mean, precipitation and snowfall.
| Month | High | Low | Mean | Rain & snow | Snow |
|---|---|---|---|---|---|
| January | −11.4°C | −21.9°C | −16.7°C | 18 mm | 25 cm |
| February | −8.5°C | −19.7°C | −14.1°C | 14 mm | 17 cm |
| March | −1.6°C | −12.5°C | −7.0°C | 24 mm | 19 cm |
| April | 9.6°C | −3.3°C | 3.1°C | 27 mm | 8 cm |
| May | 17.4°C | 3.2°C | 10.3°C | 65 mm | 4 cm |
| June | 22.6°C | 9.7°C | 16.2°C | 98 mm | 0 cm |
| July | 24.9°C | 11.8°C | 18.4°C | 72 mm | 0 cm |
| August | 25.1°C | 10.2°C | 17.7°C | 56 mm | 0 cm |
| September | 19.5°C | 4.9°C | 12.2°C | 43 mm | under 1 cm |
| October | 10.1°C | −2.2°C | 4.0°C | 32 mm | 6 cm |
| November | −0.3°C | −10.3°C | −5.3°C | 20 mm | 21 cm |
| December | −8.6°C | −18.5°C | −13.6°C | 22 mm | 29 cm |
| Year | 8.2°C | −4.0°C | 2.1°C | 489 mm | 128 cm |
February strays furthest from its normal year to year, by 4.2°C; July the least
The thirty-year records stretch furthest in March: a low of −38.4°C in 2003 and a high of 22.6°C in 2012.
Where Cornwallis’s numbers come from
Averages over 30 years, not a forecast.
- Normals: Environment and Climate Change Canada’s 1991–2020 normals, Brandon: the nearest of its locations with every month’s temperatures.
- Comparisons: the 2,500-plus towns and neighbourhoods of Canada, each read from its closest normals location; whole cities and reserves aren’t counted.
- Not on this page: a sunshine figure (ECCC published none for 1991–2020) and any lapse-rate correction for height, as the town has no elevation here.
Canadian Climate Normals 1991–2020 · ECCC Data Services End-use Licence. Data Source: Environment and Climate Change Canada
Questions about Cornwallis’s climate
How warm does Cornwallis get in summer?
Summer peaks in August: a typical afternoon reaches 25.1°C.
How cold does Cornwallis get in winter?
A typical January night falls to −21.9°C, the year’s low point.
How much rain and snow does Cornwallis get?
Precipitation totals 489 mm a year, with June the wettest month (98 mm) and February the driest (14 mm).
How long does snow stay on the ground?
About 138 days a year count as snow-covered, with 1 cm or more.
Are these figures for Cornwallis itself?
No. ECCC measures normals at Brandon, not in Cornwallis; the page uses the nearest it has.
Data Source: Environment and Climate Change Canada · ECCC Data Services End-use Licence Today’s forecast for Cornwallis →
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).