Current Conditions

Alliston, Ontario

40°F5°C

Clear

Feels like36°F2°C

Wind

NE 7 mph12 km/h

Humidity

87%

Cloud Cover

29%

As of Tuesday, September 22, 2026 at 4:47 AM EDT

Today's Outlook

Day

Mostly clear and mild, with a high of 63°F17°C and morning low of 41°F5°C. Breezy from the ENE at 8 to 9 mph13 to 14 km/h. Dry air.

Night

Mostly clear, with a low around 40°F5°C. Breezy from the ENE at 7 mph11 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Clear	High 63°F17°C	Low 40°F5°CFeels 36°F2°C	Precip 0 in0 mm—	Cloud 10%	Wind ENE 8 mph12 km/h	Tuesday: Mostly clear and mild, with a high of 63°F17°C and morning low of 41°F5°C. Breezy from the ENE at 8 to 9 mph13 to 14 km/h. Dry air. Tuesday Night: Mostly clear, with a low around 40°F5°C. Breezy from the ENE at 7 mph11 km/h.
Clear	High 66°F19°C	Low 41°F5°CFeels 36°F2°C	Precip 0 in0 mm—	Cloud 8%	Wind E 8 mph12 km/h	Wednesday: Mostly clear and mild, with a high of 66°F19°C and morning low of 43°F6°C. Breezy from the E at 9 to 10 mph14 to 16 km/h. Dry air. Wednesday Night: Mostly clear, with a low around 41°F5°C. Breezy from the E at 6 to 7 mph10 to 11 km/h.
Clear	High 67°F19°C	Low 40°F5°CFeels 37°F3°C	Precip 0 in0 mm—	Cloud 4%	Wind E 5 mph8 km/h	Thursday: Mostly clear and mild, with a high of 67°F19°C and morning low of 42°F6°C. Light wind from the E around 5 mph9 km/h. Dry air. Thursday Night: Mostly clear, with a low around 40°F5°C. Light wind from the ENE around 5 mph7 km/h.
Partly Cloudy	High 67°F20°C	Low 41°F5°CFeels 38°F4°C	Precip 0 in0 mm—	Cloud 41%	Wind N 5 mph8 km/h	Friday: Mostly cloudy and mild, with a high of 67°F20°C and morning low of 41°F5°C. Light wind from the N around 5 mph8 km/h. Dry air. Friday Night: Partly cloudy, with a low around 41°F5°C. Breezy from the N at 5 to 7 mph8 to 11 km/h.
Clear	High 70°F21°C	Low 44°F7°CFeels 41°F5°C	Precip 0 in0 mm—	Cloud 36%	Wind N 7 mph11 km/h	Saturday: Partly cloudy and warm, with a high of 70°F21°C and morning low of 45°F7°C. Breezy from the N at 7 to 8 mph11 to 14 km/h. Dry air. Saturday Night: Partly cloudy, with a low around 44°F7°C. Breezy from the NNW at 7 to 8 mph11 to 12 km/h.
Partly Cloudy	High 69°F21°C	Low 48°F9°CFeels 45°F7°C	Precip 0 in0.1 mm5%	Cloud 58%	Wind N 7 mph11 km/h	Sunday: Mostly cloudy and warm, with a high of 69°F21°C and morning low of 48°F9°C. Breezy from the N at 7 to 8 mph12 to 13 km/h. Dry air. Sunday Night: Mostly cloudy, with a low around 48°F9°C. Light wind from the NNW around 6 mph10 km/h.
Clear	High 69°F21°C	Low 49°F10°C	Precip 0.01 in0.3 mm4%	Cloud 39%	Wind NNW 6 mph9 km/h	Monday: Partly cloudy and warm, with a high of 69°F21°C and morning low of 49°F10°C. Light wind from the NNW around 6 mph9 km/h. Dry air. Monday Night: Partly cloudy, with a low around 49°F10°C. Light wind from the NNW around 5 mph8 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	TuesdaySep 22	63°F17°C	40°F5°C Feels 36°F2°C	0 in0 mm· —	10%	Clear	ENE 8 mph12 km/h
DayMostly clear and mild, with a high of 63°F17°C and morning low of 41°F5°C. Breezy from the ENE at 8 to 9 mph13 to 14 km/h. Dry air. NightMostly clear, with a low around 40°F5°C. Breezy from the ENE at 7 mph11 km/h.
	WednesdaySep 23	66°F19°C	41°F5°C Feels 36°F2°C	0 in0 mm· —	8%	Clear	E 8 mph12 km/h
DayMostly clear and mild, with a high of 66°F19°C and morning low of 43°F6°C. Breezy from the E at 9 to 10 mph14 to 16 km/h. Dry air. NightMostly clear, with a low around 41°F5°C. Breezy from the E at 6 to 7 mph10 to 11 km/h.
	ThursdaySep 24	67°F19°C	40°F5°C Feels 37°F3°C	0 in0 mm· —	4%	Clear	E 5 mph8 km/h
DayMostly clear and mild, with a high of 67°F19°C and morning low of 42°F6°C. Light wind from the E around 5 mph9 km/h. Dry air. NightMostly clear, with a low around 40°F5°C. Light wind from the ENE around 5 mph7 km/h.
	FridaySep 25	67°F20°C	41°F5°C Feels 38°F4°C	0 in0 mm· —	41%	Partly Cloudy	N 5 mph8 km/h
DayMostly cloudy and mild, with a high of 67°F20°C and morning low of 41°F5°C. Light wind from the N around 5 mph8 km/h. Dry air. NightPartly cloudy, with a low around 41°F5°C. Breezy from the N at 5 to 7 mph8 to 11 km/h.
	SaturdaySep 26	70°F21°C	44°F7°C Feels 41°F5°C	0 in0 mm· —	36%	Clear	N 7 mph11 km/h
DayPartly cloudy and warm, with a high of 70°F21°C and morning low of 45°F7°C. Breezy from the N at 7 to 8 mph11 to 14 km/h. Dry air. NightPartly cloudy, with a low around 44°F7°C. Breezy from the NNW at 7 to 8 mph11 to 12 km/h.
	SundaySep 27	69°F21°C	48°F9°C Feels 45°F7°C	0 in0.1 mm· 5%	58%	Partly Cloudy	N 7 mph11 km/h
DayMostly cloudy and warm, with a high of 69°F21°C and morning low of 48°F9°C. Breezy from the N at 7 to 8 mph12 to 13 km/h. Dry air. NightMostly cloudy, with a low around 48°F9°C. Light wind from the NNW around 6 mph10 km/h.
	MondaySep 28	69°F21°C	49°F10°C	0.01 in0.3 mm· 4%	39%	Clear	NNW 6 mph9 km/h
DayPartly cloudy and warm, with a high of 69°F21°C and morning low of 49°F10°C. Light wind from the NNW around 6 mph9 km/h. Dry air. NightPartly cloudy, with a low around 49°F10°C. Light wind from the NNW around 5 mph8 km/h.
	TuesdaySep 29	71°F22°C	48°F9°C	0 in0.1 mm· 2%	40%	Partly Cloudy	WSW 5 mph7 km/h
DayPartly cloudy and warm, with a high of 71°F22°C and morning low of 48°F9°C. Light wind from the W around 4 mph7 km/h. Dry air. NightPartly cloudy, with a low around 48°F9°C. Light wind from the SW around 5 mph8 km/h.
	WednesdaySep 30	69°F21°C	51°F10°C	0.07 in1.9 mm· 18%	69%	Drizzle	SSE 7 mph11 km/h
DayMostly cloudy and warm, with a high of 69°F21°C and morning low of 52°F11°C. Breezy from the SSE at 7 to 8 mph12 to 14 km/h. 15% chance of drizzle throughout the day. NightMostly cloudy, with a low around 51°F10°C. Breezy from the SSE at 7 to 8 mph11 to 12 km/h. 18% chance of drizzle throughout the night.
	ThursdayOct 1	66°F19°C	54°F12°C	0.16 in4 mm· 28%	72%	Light Rain	S 8 mph13 km/h
DayMostly cloudy and mild, with a high of 66°F19°C and morning low of 54°F12°C. Breezy from the S at 8 to 9 mph13 to 14 km/h. 28% chance of light rain throughout the day. NightMostly cloudy, with a low around 54°F12°C. Breezy from the S at 7 to 8 mph12 to 12 km/h. 23% chance of showers throughout the night.
	FridayOct 2	64°F18°C	52°F11°C	0.12 in3 mm· 26%	68%	Drizzle	WNW 8 mph12 km/h
DayMostly cloudy and mild, with a high of 64°F18°C and morning low of 52°F11°C. Breezy from the WNW at 8 to 9 mph13 to 14 km/h. 26% chance of drizzle throughout the day. NightMostly cloudy, with a low around 52°F11°C. Breezy from the W at 7 mph11 km/h. 22% chance of drizzle throughout the night.
	SaturdayOct 3	63°F17°C	50°F10°C	0.08 in2.1 mm· 19%	66%	Drizzle	W 7 mph12 km/h
DayMostly cloudy and mild, with a high of 63°F17°C and morning low of 50°F10°C. Breezy from the WNW at 8 mph12 km/h. 19% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 51°F10°C. Breezy from the WSW at 7 mph11 km/h. 15% chance of drizzle throughout the night.
	SundayOct 4	64°F18°C	50°F10°C Feels 47°F8°C	0.07 in1.9 mm· 18%	61%	Drizzle	SW 7 mph11 km/h
DayMostly cloudy and mild, with a high of 64°F18°C and morning low of 50°F10°C. Breezy from the SW at 7 to 8 mph12 to 13 km/h. 18% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 50°F10°C. Breezy from the SW at 7 mph11 km/h. 14% chance of drizzle throughout the night.
	MondayOct 5	64°F18°C	49°F9°C Feels 46°F8°C	0.07 in1.9 mm· 20%	61%	Drizzle	WSW 7 mph12 km/h
DayMostly cloudy and mild, with a high of 64°F18°C and morning low of 49°F9°C. Breezy from the WSW at 8 mph13 km/h. 20% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 49°F9°C. Breezy from the WSW at 7 mph11 km/h. 17% chance of drizzle throughout the night.
	TuesdayOct 6	63°F17°C	49°F9°C Feels 46°F8°C	0.1 in2.5 mm· 20%	65%	Drizzle	WSW 7 mph12 km/h
DayMostly cloudy and mild, with a high of 63°F17°C and morning low of 49°F9°C. Breezy from the WSW at 8 mph13 km/h. 20% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 49°F10°C. Breezy from the WSW at 7 mph11 km/h. 16% chance of drizzle throughout the night.

Nearby Cities

Innisfil15 mi24 km Bolton20 mi32 km Orangeville20 mi32 km Barrie20 mi32 km Caledon21 mi33 km Keswick21 mi34 km

About This Forecast

This forecast is powered by WeatherMesh, the world's most advanced and accurate weather model powered by AI. WeatherMesh is built on proprietary data from WindBorne's Global Sounding Balloon constellation — the world's largest fleet of autonomous, long-duration weather balloons — collecting observations across 100% of Earth, including over oceans and remote regions where no other data exists.

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Coordinates: 44.1501°N, 79.8663°W·Elevation: 223m·Timezone: America/Toronto·Population: 18,809