Photo: Joe Mabel (on Flickr as Joe Mabel from Seattle, US) · CC BY-SA 3.0Ice rarely forms: Oshawa sees fewer frosts than 84% of Canadian towns
High summer brings afternoon highs near 25.7°C. Expect the most rain and snow in June and the least in February. Garden chairs stay out from June to September, the months with highs of 21–26°C.
1991–2020 normals from ECCC’s Oshawa station, 1.9 km west.
A year in Oshawa at a glance
Each month’s typical high and low, in °C.
What stands out about Oshawa’s climate
Compared with Canadian towns, with its place among towns of 2,500+ in Ontario beside it.
What a year in Oshawa feels like
Seasons and months as ECCC’s 1991–2020 normals give them: a typical day’s high and low.
About 130 frosts and 107 warm days a year
The frost season runs October to April, and January freezes nearly every night. Heat of 30°C or more comes on about 4 days a year.
Frost days by month
Average days at 0°C or below
Days above 20°C by month
Average days
About 906 mm of rain and snow a year
On about 115 days a year, 1 mm or more falls.
Rain and snow by month
Millimetres
Rain alone by month
Millimetres
About 102 cm of snow a year
The snow season runs November to April; January brings the most, about 34 cm.
Snowfall by month
Centimetres
Snow on the ground by month
Centimetres at month’s end
Heating a home in Oshawa
92% 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. In heating terms, homes need less heating than 81% of Canadian towns.
Living with Oshawa’s climate
Gardening, time outside, winter cold and summer heat, from the 1991–2020 normals.
The frost-free stretch runs from about 30 April to about 15 October, some 167 days in a normal year.
Plan time outside for Jun, Jul, Aug and Sep: highs of 17–27°C and nights no colder than 8°C.
Parks & trails →The normals describe a typical year, not its worst days; the hazards page covers Oshawa’s.
Flood & hazards →ECCC’s normals location: Oshawa
Oshawa is a composite: ECCC joins 2 stations’ readings to make its 1991–2020 normals.
| Distance from the town | 1.9 km west |
| Station altitude | 140 m |
| Completeness | at least 20 years |
| WMO standard normals | No |
| Coldest reading, 1991–2020 | −28.0°C |
| Hottest reading, 1991–2020 | 37.1°C |
| Next-nearest location | Toronto Buttonville (Airport), 42 km |
How Oshawa 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 Ontario.
Nearby towns’ climate
Places around Oshawa whose figures come from another normals location. The nearest places to Oshawa with figures are 31–45 km away.
| Town | July high | January low | Rain & snow |
|---|---|---|---|
| Oshawa | 25.7°C | −8.9°C | 906 mm |
| Uxbridge 31 km · Udora | 26.3°C 0.6°C warmer | −11.7°C 2.8°C colder | 883 mm |
| Stouffville 34 km · Toronto Buttonville (Airport) | 27.3°C 1.6°C warmer | −10.1°C 1.2°C colder | 862 mm |
| Port Hope 44 km · Cobourg | 23.6°C 2.1°C cooler | −8.7°C about the same | 840 mm |
| Millbrook 45 km · Peterborough | 26.6°C 0.9°C warmer | −12.8°C 3.9°C colder | 840 mm |
Oshawa weather by month
Each month’s normals, 1991–2020: high, low, mean, precipitation and snowfall.
| Month | High | Low | Mean | Rain & snow | Snow |
|---|---|---|---|---|---|
| January | −1.1°C | −8.9°C | −5.0°C | 75 mm | 34 cm |
| February | −0.2°C | −8.3°C | −4.2°C | 54 mm | 26 cm |
| March | 4.5°C | −3.9°C | 0.3°C | 54 mm | 11 cm |
| April | 10.6°C | 1.7°C | 6.2°C | 87 mm | 2 cm |
| May | 17.5°C | 7.6°C | 12.6°C | 85 mm | 0 cm |
| June | 22.7°C | 12.9°C | 17.8°C | 94 mm | 0 cm |
| July | 25.7°C | 15.8°C | 20.9°C | 86 mm | 0 cm |
| August | 24.8°C | 15.4°C | 20.1°C | 74 mm | 0 cm |
| September | 20.9°C | 11.4°C | 16.2°C | 86 mm | 0 cm |
| October | 13.6°C | 5.3°C | 9.5°C | 72 mm | under 1 cm |
| November | 7.5°C | 0.3°C | 3.9°C | 73 mm | 5 cm |
| December | 2.2°C | −4.6°C | −1.2°C | 68 mm | 25 cm |
| Year | 12.4°C | 3.7°C | 8.1°C | 906 mm | 102 cm |
March: −25.2°C at its coldest, 23.3°C at its warmest
Year to year, February varies most (a standard deviation of 3.0°C around −4.2°C) and October least (0.9°C).
Where Oshawa’s numbers come from
Averages over 30 years, not a forecast.
- Normals: Environment and Climate Change Canada’s 1991–2020 normals, Oshawa: the nearest of its locations with every month’s temperatures.
- Comparisons: Canada’s towns and neighbourhoods of 2,500+ (no city totals, no reserves), each through its own nearest location.
- 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 Oshawa’s climate
How warm does Oshawa get in summer?
Peak warmth comes in July, at about 25.7°C by mid-afternoon.
How cold does Oshawa get in winter?
The coldest nights come in January, averaging −8.9°C.
How much rain and snow does Oshawa get?
Around 906 mm a year in all, from 94 mm in June down to 54 mm in February.
How long does snow stay on the ground?
In a normal winter there are about 55 days with at least 1 cm of snow lying.
Are these figures for Oshawa itself?
They are: the normals station that gives them stands in Oshawa.
Data Source: Environment and Climate Change Canada · ECCC Data Services End-use Licence Today’s forecast for Oshawa →
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).