Current Conditions
Thornhill, Ontario
Wind
SE 6 mph10 km/h
Humidity
83%
Cloud Cover
99%
As of Tuesday, September 8, 2026 at 11:18 PM EDT
Today's Outlook
Night
Overcast, with a low around 66°F19°C. Breezy from the SW at 8 to 12 mph13 to 19 km/h. 89% chance of light rain before dawn.
7-Day Forecast
| Day | Condition | High (°F) | Low (°F) | Precip (mm) | Cloud Cover (%) | Wind (mph) | |
|---|---|---|---|---|---|---|---|
| Rain | High 73°F23°C | Low 66°F19°C | Precip 0.43 in11 mm97% | Cloud 92% | Wind SW 9 mph14 km/h | Wednesday: Overcast and warm, with a high of 73°F23°C and morning low of 68°F20°C. Breezy from the SW at 10 to 13 mph16 to 21 km/h. 97% chance of rain throughout the day. Humid. Wednesday Night: Overcast, with a low around 66°F19°C. Breezy from the SW at 8 to 12 mph13 to 19 km/h. 89% chance of light rain before dawn. | |
| Partly Cloudy | High 73°F23°C | Low 58°F15°C | Precip 0 in0 mm— | Cloud 61% | Wind WNW 9 mph15 km/h | Thursday: Overcast and warm, with a high of 73°F23°C and morning low of 64°F18°C. Breezy from the WNW at 10 to 11 mph16 to 18 km/h. Thursday Night: Partly cloudy, with a low around 58°F15°C. Breezy from the WNW at 9 to 11 mph14 to 17 km/h. | |
| Clear | High 72°F22°C | Low 52°F11°C | Precip 0 in0 mm— | Cloud 12% | Wind W 5 mph8 km/h | Friday: Mostly clear and warm, with a high of 72°F22°C and morning low of 53°F12°C. Light wind from the W around 4 mph7 km/h. Friday Night: Mostly clear, with a low around 52°F11°C. Light wind from the WSW around 6 mph9 km/h. | |
| Partly Cloudy | High 75°F24°C | Low 56°F14°C | Precip 0.03 in0.8 mm9% | Cloud 48% | Wind SSE 6 mph10 km/h | Saturday: Partly cloudy and warm, with a high of 75°F24°C and morning low of 58°F15°C. Breezy from the SSE at 7 to 8 mph11 to 13 km/h. Saturday Night: Mostly cloudy, with a low around 56°F14°C. Light wind from the SSE around 6 mph10 km/h. | |
| Drizzle | High 75°F24°C | Low 60°F16°C | Precip 0.05 in1.3 mm12% | Cloud 45% | Wind WNW 9 mph14 km/h | Sunday: Mostly cloudy and warm, with a high of 75°F24°C and morning low of 65°F18°C. Breezy from the WNW at 9 to 11 mph14 to 18 km/h. 12% chance of drizzle throughout the day. Sunday Night: Partly cloudy, with a low around 60°F16°C. Breezy from the WNW at 8 to 10 mph14 to 16 km/h. | |
| Partly Cloudy | High 68°F20°C | Low 55°F13°C | Precip 0.03 in0.7 mm9% | Cloud 48% | Wind NNW 7 mph12 km/h | Monday: Mostly cloudy and warm, with a high of 68°F20°C and morning low of 55°F13°C. Breezy from the NNW at 7 mph11 km/h. Dry air. Monday Night: Partly cloudy, with a low around 55°F13°C. Breezy from the NNW at 8 mph12 km/h. | |
| Showers | High 76°F24°C | Low 59°F15°C | Precip 0.15 in3.9 mm34% | Cloud 69% | Wind SSW 11 mph18 km/h | Tuesday: Mostly cloudy and warm, with a high of 76°F24°C and morning low of 63°F17°C. Breezy from the SSW at 12 to 14 mph20 to 23 km/h. 32% chance of light rain throughout the day. Tuesday Night: Mostly cloudy, with a low around 59°F15°C. Breezy from the S at 9 to 10 mph15 to 16 km/h. 34% chance of showers throughout the night. |
15-Day Forecast
| Day | High | Low | Precip | Cloud Cover | Condition | Wind | |
|---|---|---|---|---|---|---|---|
| WednesdaySep 9 | 73°F23°C | 66°F19°C | 0.43 in11 mm· 97% | 92% | Rain | SW 9 mph14 km/h | |
DayOvercast and warm, with a high of 73°F23°C and morning low of 68°F20°C. Breezy from the SW at 10 to 13 mph16 to 21 km/h. 97% chance of rain throughout the day. Humid. NightOvercast, with a low around 66°F19°C. Breezy from the SW at 8 to 12 mph13 to 19 km/h. 89% chance of light rain before dawn. | |||||||
| ThursdaySep 10 | 73°F23°C | 58°F15°C | 0 in0 mm· — | 61% | Partly Cloudy | WNW 9 mph15 km/h | |
DayOvercast and warm, with a high of 73°F23°C and morning low of 64°F18°C. Breezy from the WNW at 10 to 11 mph16 to 18 km/h. NightPartly cloudy, with a low around 58°F15°C. Breezy from the WNW at 9 to 11 mph14 to 17 km/h. | |||||||
| FridaySep 11 | 72°F22°C | 52°F11°C | 0 in0 mm· — | 12% | Clear | W 5 mph8 km/h | |
DayMostly clear and warm, with a high of 72°F22°C and morning low of 53°F12°C. Light wind from the W around 4 mph7 km/h. NightMostly clear, with a low around 52°F11°C. Light wind from the WSW around 6 mph9 km/h. | |||||||
| SaturdaySep 12 | 75°F24°C | 56°F14°C | 0.03 in0.8 mm· 9% | 48% | Partly Cloudy | SSE 6 mph10 km/h | |
DayPartly cloudy and warm, with a high of 75°F24°C and morning low of 58°F15°C. Breezy from the SSE at 7 to 8 mph11 to 13 km/h. NightMostly cloudy, with a low around 56°F14°C. Light wind from the SSE around 6 mph10 km/h. | |||||||
| SundaySep 13 | 75°F24°C | 60°F16°C | 0.05 in1.3 mm· 12% | 45% | Drizzle | WNW 9 mph14 km/h | |
DayMostly cloudy and warm, with a high of 75°F24°C and morning low of 65°F18°C. Breezy from the WNW at 9 to 11 mph14 to 18 km/h. 12% chance of drizzle throughout the day. NightPartly cloudy, with a low around 60°F16°C. Breezy from the WNW at 8 to 10 mph14 to 16 km/h. | |||||||
| MondaySep 14 | 68°F20°C | 55°F13°C | 0.03 in0.7 mm· 9% | 48% | Partly Cloudy | NNW 7 mph12 km/h | |
DayMostly cloudy and warm, with a high of 68°F20°C and morning low of 55°F13°C. Breezy from the NNW at 7 mph11 km/h. Dry air. NightPartly cloudy, with a low around 55°F13°C. Breezy from the NNW at 8 mph12 km/h. | |||||||
| TuesdaySep 15 | 76°F24°C | 59°F15°C | 0.15 in3.9 mm· 34% | 69% | Showers | SSW 11 mph18 km/h | |
DayMostly cloudy and warm, with a high of 76°F24°C and morning low of 63°F17°C. Breezy from the SSW at 12 to 14 mph20 to 23 km/h. 32% chance of light rain throughout the day. NightMostly cloudy, with a low around 59°F15°C. Breezy from the S at 9 to 10 mph15 to 16 km/h. 34% chance of showers throughout the night. | |||||||
| WednesdaySep 16 | 72°F22°C | 62°F17°C | 0.14 in3.6 mm· 26% | 61% | Showers | NW 7 mph11 km/h | |
DayMostly cloudy and warm, with a high of 72°F22°C and morning low of 62°F17°C. Breezy from the NW at 7 mph11 km/h. 18% chance of showers throughout the day. NightMostly cloudy, with a low around 62°F17°C. Breezy from the NW at 7 to 9 mph12 to 14 km/h. 26% chance of showers throughout the night. | |||||||
| ThursdaySep 17 | 71°F22°C | 59°F15°C | 0.15 in3.8 mm· 26% | 65% | Showers | S 8 mph12 km/h | |
DayMostly cloudy and warm, with a high of 71°F22°C and morning low of 60°F16°C. Breezy from the S at 8 to 9 mph13 to 14 km/h. 26% chance of showers throughout the day. NightMostly cloudy, with a low around 59°F15°C. Breezy from the N at 7 to 9 mph12 to 14 km/h. 25% chance of showers throughout the night. | |||||||
| FridaySep 18 | 69°F20°C | 58°F15°C | 0.15 in3.8 mm· 24% | 59% | Showers | WNW 10 mph16 km/h | |
DayMostly cloudy and warm, with a high of 69°F20°C and morning low of 61°F16°C. Breezy from the WNW at 10 to 11 mph16 to 17 km/h. 23% chance of drizzle throughout the day. NightMostly cloudy, with a low around 58°F15°C. Breezy from the WNW at 9 to 10 mph15 to 15 km/h. 24% chance of showers throughout the night. | |||||||
| SaturdaySep 19 | 65°F18°C | 55°F13°C | 0.11 in2.7 mm· 17% | 53% | Drizzle | WNW 9 mph15 km/h | |
DayMostly cloudy and mild, with a high of 65°F18°C and morning low of 55°F13°C. Breezy from the W at 9 to 10 mph15 to 16 km/h. 15% chance of drizzle throughout the day. Dry air. NightPartly cloudy, with a low around 55°F13°C. Breezy from the WNW at 9 mph14 km/h. 17% chance of drizzle throughout the night. | |||||||
| SundaySep 20 | 62°F17°C | 52°F11°C | 0.09 in2.4 mm· 15% | 54% | Drizzle | NW 8 mph14 km/h | |
DayMostly cloudy and mild, with a high of 62°F17°C and morning low of 52°F11°C. Breezy from the NW at 9 mph14 km/h. 15% chance of drizzle throughout the day. Dry air. NightPartly cloudy, with a low around 52°F11°C. Breezy from the NW at 8 mph13 km/h. 15% chance of drizzle throughout the night. | |||||||
| MondaySep 21 | 62°F17°C | 49°F10°C Feels 46°F8°C | 0.11 in2.7 mm· 17% | 50% | Showers | N 8 mph13 km/h | |
DayMostly cloudy and mild, with a high of 62°F17°C and morning low of 50°F10°C. Breezy from the NNW at 9 mph14 km/h. 17% chance of drizzle throughout the day. Dry air. NightPartly cloudy, with a low around 49°F10°C. Breezy from the N at 8 mph13 km/h. 14% chance of showers throughout the night. | |||||||
| TuesdaySep 22 | 64°F18°C | 51°F10°C | 0.11 in2.9 mm· 15% | 50% | Showers | ENE 8 mph13 km/h | |
DayMostly cloudy and mild, with a high of 64°F18°C and morning low of 51°F11°C. Breezy from the SE at 9 mph14 km/h. 15% chance of showers throughout the day. Dry air. NightPartly cloudy, with a low around 51°F10°C. Breezy from the NNE at 8 mph13 km/h. 14% chance of drizzle throughout the night. | |||||||
| WednesdaySep 23 | 65°F19°C | 52°F11°C | 0.07 in1.9 mm· 15% | 53% | Drizzle | S 8 mph13 km/h | |
DayMostly cloudy and mild, with a high of 65°F19°C and morning low of 53°F11°C. Breezy from the S at 8 to 9 mph13 to 14 km/h. 13% chance of drizzle throughout the day. Dry air. NightPartly cloudy, with a low around 52°F11°C. Breezy from the SSE at 8 mph13 km/h. 15% chance of drizzle throughout the night. | |||||||
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Coordinates: 43.8150°N, 79.4242°W·Elevation: 175m·Timezone: America/Toronto·Population: 115,292