Climate averages 1991–2020
Thornhill weather
in August.
A warm, moderately wet month: the 2nd warmest and the 5th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
August is a warm month in Thornhill: daytime highs average 24.8°C and nights cool to about 17.2°C. By daytime temperature it is the 2nd warmest of the 12 months.
Expect about 65 mm of rain on roughly 9 days, which makes August a moderately wet month (the 5th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 14 h 00 min on an average August day.
The nearest other city in this atlas is Richmond Hill (6 km away). In August its highs average 24.8°C, about as warm as Thornhill, with 65 mm of rain.
Among the 86 cities listed in Canada, Thornhill ranks joint 19th of 86 for the warmest August highs and joint 17th of 86 for the driest August (rainfall, lowest first). The mean August high of those 86 cities is 23.8°C; Thornhill is 1.0°C warmer than that mean.
From August to September, average highs fall by 3.8°C to 21.0°C, and monthly rainfall rises from 65 mm to 69 mm.
The annual picture
August in context
Monthly precipitation
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Thornhill climate table
| Month | Average highHigh / low | Average low | Precipitation mm/month | Wet days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | -1.4°C-8.6°C | -8.6°C | 60 | 10.2 | 9.39 h |
| February | -0.8°C-9.2°C | -9.2°C | 49 | 7.9 | 10.410 h |
| March | 3.8°C-4.6°C | -4.6°C | 57 | 9.5 | 11.912 h |
| April | 10.2°C1.8°C | 1.8°C | 77 | 10.7 | 13.413 h |
| May | 16.9°C8.2°C | 8.2°C | 72 | 10.1 | 14.715 h |
| June | 22.4°C14.2°C | 14.2°C | 77 | 10.6 | 15.415 h |
| July | 25.5°C17.5°C | 17.5°C | 71 | 9.6 | 15.115 h |
| August, selected | 24.8°C17.2°C | 17.2°C | 65 | 8.8 | 14.014 h |
| September | 21.0°C13.7°C | 13.7°C | 69 | 8.7 | 12.613 h |
| October | 14.0°C7.5°C | 7.5°C | 75 | 10.5 | 11.111 h |
| November | 7.1°C1.4°C | 1.4°C | 67 | 10.0 | 9.710 h |
| December | 1.7°C-4.0°C | -4.0°C | 61 | 10.0 | 9.09 h |
Precipitation (rain or snow, as water) is the average of the 30 separate monthly totals. A wet day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
August in nearby cities
- Richmond Hill in AugustCanada · 6 kmHigh 24.8°C · Low 16.3°C · 65 mm rain
- Vaughan in AugustCanada · 6 kmHigh 24.8°C · Low 16.5°C · 65 mm rain
- Toronto in AugustCanada · 12 kmHigh 24.5°C · Low 17.6°C · 65 mm rain
- Markham in AugustCanada · 14 kmHigh 24.9°C · Low 16.9°C · 67 mm rain
- Etobicoke in AugustCanada · 22 kmHigh 25.0°C · Low 17.4°C · 65 mm rain
- Pickering in AugustCanada · 25 kmHigh 24.1°C · Low 17.0°C · 84 mm rain
- Newmarket in AugustCanada · 26 kmHigh 24.7°C · Low 15.9°C · 78 mm rain
- Brampton in AugustCanada · 31 kmHigh 25.1°C · Low 16.2°C · 71 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Thornhill) is explained once on the Thornhill year overview and on the Sources, method and limits page.
Toronto, Etobicoke and Vaughan lie in the same rainfall cell, so their rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.