Oshawa weather in August
In August, Oshawa has daytime highs averaging 25 °C, nights around 18 °C, with 10 wet days. Figures are 1991–2020 climate normals.
- 24.7°C Average high
- 18.0°C Average low
- 10days Wet days
- 76mm Rainfall
- 14h Daylight
Daily temperatures through August
How August develops
Averages for the first, middle and last part of the month, from daily 1991–2020 normals. Chance of rain is the share of years in which that calendar day recorded more than 1 mm.
| Days | Avg high | Avg low | Chance of rain |
|---|---|---|---|
| 1–10 August | 25.3 °C | 18.5 °C | 37 % |
| 11–20 August | 24.7 °C | 18.0 °C | 33 % |
| 21–31 August | 24.1 °C | 17.5 °C | 30 % |
- Average highs fall from 25.3 °C early in August to 24.1 °C by the end of it.
- Rain is most likely over days 1–10 of August (37 % of days) and least likely over days 21–31 (30 %).
What to expect
| Measure | Typical August | Share of the month |
|---|---|---|
| Days above 25 °C | 14 of 31 | 45 % |
| Days above 30 °C | 0.6 of 31 | 2 % |
| Days below 0 °C | 0 of 31 | 0 % |
| Days with more than 1 mm rain | 10 of 31 | 33 % |
Conditions in August
| Measure | Average |
|---|---|
| Mean temperature | 21 °C |
| Record high (1991–2020) | 33 °C |
| Record low (1991–2020) | 11 °C |
| Relative humidity | 73 % |
| Wind speed | 16 km/h |
| Cloud cover | 50 % |
Where Oshawa ranks in August
| Ranking | Position | Value |
|---|---|---|
| Places with the best weather in North America in August | 38th of 50 | 85/100 |
| The coolest places in North America in August | 40th of 50 | 25 °C |
August compared with the months around it
| Month | Avg high | Rainfall | Cloud |
|---|---|---|---|
| June | 21.9 °C | 88 mm | 57 % |
| July | 25.2 °C | 82 mm | 51 % |
| August | 24.7 °C | 76 mm | 50 % |
| September | 21.0 °C | 80 mm | 52 % |
| October | 14.1 °C | 85 mm | 61 % |
See all twelve months for Oshawa
- August is the 2nd warmest month here.
- It is the 7th driest month of the year.
- It ranks 1st for least cloud cover.
- Days last about 14 hours from sunrise to sunset.
- It rains on 10 of 31 days — 33 % of the month.
- Nights are about 6.7 °C cooler than the middle of the day.
- The hottest August day on record since 1991 reached 33 °C, 8.0 °C above the usual daytime high.
QuestionsAugust in Oshawa, answered
How warm is Oshawa in August?
Daily highs average 25 °C and nights fall to about 18 °C, a spread of 6.7 °C between afternoon and dawn. That makes August the 2nd warmest month of the year here.
Does it rain much in Oshawa in August?
August averages 76 mm of rain, spread over about 10 of the 31 days — 33 % of the month. Cloud cover averages 50 % of the sky.
How long are the days in August?
Oshawa averages 14 hours between sunrise and sunset in August. Day length is computed from latitude and date, so it is exact rather than modelled — but it says nothing about how much of that time is sunny.
Data sources and method
- ERA5 / ERA5-Land reanalysis — Copernicus Climate Change Service (C3S), ECMWF. Copernicus Licence
- Open-Meteo — Open-Meteo.com. CC BY 4.0
- NOAA OISST v2.1 — NOAA Physical Sciences Laboratory. Public domain
- GeoNames — GeoNames.org. CC BY 4.0
- Normal period
- 1991–2020
- Dataset version
- era5-1991-2020-scores1.1
- Last processed
Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: daylight hours, beach and comfort scores, monthly rankings, threshold day counts, chance of a wet day by date, ten-day averages within the month. Full formulas are on the methodology page.
Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.