Oshawa climate — normals and trends
Oshawa (Canada) has a warm-summer humid continental climate (Dfb) under the Köppen-Geiger classification. Its mean annual temperature is 7.6 °C and it receives 878 mm of precipitation per year.
These figures are normals computed over 86 complete calendar years, from 1940 to 2025, using ERA5 reanalysis data from the Copernicus programme.
The warmest month is July (21.1 °C on average) and the coldest is January (-6.7 °C). Rainfall peaks in July.
Oshawa averages 136 frost days, 8 hot days (≥ 30 °C) and 126 rainy days per year.
Oshawa has warmed by +1.5 °C between 1940 and 2025, or +0.18 °C per decade. This trend is statistically significant.
The number of frost days there went from about 143 to 129 per year over the period.
The hottest day of the period reached 36.9 °C (on 2 July 1966) and the coldest -34.4 °C (on 25 December 1980).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Climate normals · ERA5
OshawaOntario
- coords
- 43.90°, -78.85°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
7.6°C
Average daily high
12.0°C
Average daily low
3.1°C
Annual rainfall
878mm
Sunshine / day
8.8h
Mean relative humidity
72%
Average peak wind
19.2km/h
Seasonal range
27.8°C
Frost days (< 0 °C)
136 d/yr
Hot days (≥ 30 °C)
8 d/yr
Rainy days (≥ 1 mm)
126 d/yr
Annual snowfall
109.9 cm
Average feels-like high
9.5 °C
Average feels-like low
-0.2 °C
Average peak gust
40.7 km/h
Tropical nights (≥ 20 °C)
8 d/yr
Solar radiation
14.3 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.5 °C
since 1940
+0.2 °C per decade · r² = 0.27 · p = < 0.001
Trend fitted by linear regression (ordinary least squares) on annual means. A trend is shown only when it is statistically significant (p < 0.05).
A climograph overlays rainfall (bars) and temperature (line): the standard reading in climatology, where you can see at a glance whether the warm season is also the dry one.
Records for the period
Hottest day
36.9 °C
2 July 1966
Coldest day
-34.4 °C
25 December 1980
Wettest day
86 mm
14 July 1945
Windiest day
50.7 km/h
15 October 1954
Strongest gust
110.2 km/h
6 April 1985
Hottest feels-like
40.1 °C
21 July 2011
Coldest feels-like
-39.6 °C
25 December 1980
Snowiest day
26.5 cm
11 December 1992
Sunniest day
15.0 h
20 June 2013
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and see how it compares to normal — warmer, drier or more extreme than usual?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | -3.0 °C | -0.3 °C | 37 mm | -23 mm |
| Feb | -2.5 °C | -0.8 °C | 74 mm | +18 mm |
| Mar | 6.2 °C | +2.7 °C | 91 mm | +24 mm |
| Apr | 11.1 °C | 0.0 °C | 64 mm | -16 mm |
| May | 17.5 °C | -0.5 °C | 97 mm | +17 mm |
| Jun | 24.5 °C | +1.2 °C | 40 mm | -40 mm |
| Jul | 28.1 °C | +2.0 °C | 44 mm | -36 mm |
| Aug | 25.6 °C | +0.5 °C | 59 mm | -19 mm |
| Sep | 22.8 °C | +2.1 °C | 37 mm | -42 mm |
| Oct | 15.5 °C | +1.6 °C | 82 mm | +6 mm |
| Nov | 5.8 °C | -0.9 °C | 58 mm | -17 mm |
| Dec | -0.5 °C | -0.8 °C | 98 mm | +28 mm |
The year's extremes
What was the weather like that day?
Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.
Frequently asked questions
What is the climate of Oshawa?
Oshawa has a warm-summer humid continental climate (Köppen Dfb). Over 1940-2025, the average annual temperature is 7.6 °C and it receives 878 mm of precipitation per year.
What is the hottest day ever recorded in Oshawa?
The hottest day measured in Oshawa between 1940 and 2025 was 2 July 1966, reaching 36.9 °C.
What is the coldest day in Oshawa?
The coldest day measured in Oshawa between 1940 and 2025 was 25 December 1980, at -34.4 °C.
Does it snow in Oshawa?
Yes. Oshawa gets on average 109.9 cm of snow per year and has around 136 frost days.
Has the climate of Oshawa warmed?
Yes: Oshawa warmed by +1.5 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Oshawa?
The wettest day measured in Oshawa between 1940 and 2025 was 14 July 1945, with 86 mm of rain in 24 hours.
What was the windiest day in Oshawa?
The windiest day measured in Oshawa between 1940 and 2025 was 15 October 1954, with winds reaching 50.7 km/h.
What is the warmest month in Oshawa?
The warmest month in Oshawa is July (21.1 °C on average); the coldest is January (-6.7 °C).
How much does it rain in Oshawa?
Oshawa receives on average 878 mm of precipitation per year, spread over about 126 rainy days.
Is it sunny in Oshawa?
Oshawa gets on average 8.8 hours of sunshine per day, roughly 3,212 hours per year over 1940-2025.
What is the biggest single-day snowfall in Oshawa?
The heaviest 24-hour snowfall measured in Oshawa between 1940 and 2025 was 11 December 1992, with 26.5 cm.
Are there tropical nights in Oshawa?
Yes: Oshawa has on average 8 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Oshawa?
In Oshawa, between 1940 and 2025, the highest apparent temperature reached 40.1 °C on 21 July 2011, and the lowest was -39.6 °C on 25 December 1980.
Compare Oshawa with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Oshawa