Climate averages 1991–2020
Thornhill weather
in January.
A freezing month with moderate precipitation: the coolest and the 3rd driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
January is a freezing month in Thornhill: daytime highs average -1.4°C and nights cool to about -8.6°C. By daytime temperature it is the coolest month of the year.
Expect about 60 mm of precipitation on roughly 10 days, which makes January a month with moderate precipitation (the 3rd driest of the 12 months). Daylight, from sunrise to sunset, lasts about 9 h 19 min on an average January day.
The nearest other city in this atlas is Richmond Hill (6 km away). In January its highs average -2.0°C, 0.6°C cooler than Thornhill, with 60 mm of precipitation.
Among the 86 cities listed in Canada, Thornhill ranks 33rd of 86 for the warmest January highs and joint 19th of 86 for the driest January (precipitation, lowest first). The mean January high of those 86 cities is -2.3°C; Thornhill is 0.9°C warmer than that mean.
From January to February, average highs rise by 0.6°C to -0.8°C, and monthly precipitation falls from 60 mm to 49 mm.
The annual picture
January 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, selected | -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 | 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
January in nearby cities
- Richmond Hill in JanuaryCanada · 6 kmHigh -2.0°C · Low -10.1°C · 60 mm precipitation
- Vaughan in JanuaryCanada · 6 kmHigh -1.8°C · Low -9.4°C · 60 mm precipitation
- Toronto in JanuaryCanada · 12 kmHigh -1.3°C · Low -7.9°C · 60 mm precipitation
- Markham in JanuaryCanada · 14 kmHigh -1.7°C · Low -9.5°C · 81 mm precipitation
- Etobicoke in JanuaryCanada · 22 kmHigh -1.1°C · Low -7.8°C · 60 mm precipitation
- Pickering in JanuaryCanada · 25 kmHigh -2.2°C · Low -9.5°C · 62 mm precipitation
- Newmarket in JanuaryCanada · 26 kmHigh -2.6°C · Low -11.3°C · 57 mm precipitation
- Brampton in JanuaryCanada · 31 kmHigh -1.8°C · Low -9.9°C · 60 mm precipitation
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.