Current Conditions

Alliston, Ontario

69°F21°C

Rain

Wind

SSE 7 mph11 km/h

Humidity

97%

Cloud Cover

96%

As of Wednesday, September 2, 2026 at 2:50 AM EDT

Today's Outlook

Day

Overcast and warm, with a high of 80°F27°C and morning low of 69°F21°C. Breezy from the SW at 7 to 8 mph11 to 12 km/h. 97% chance of rain throughout the day. Heavy, humid air.

Night

Overcast, with a low around 66°F19°C. Breezy from the SSW at 6 to 7 mph9 to 11 km/h. 95% chance of rain throughout the night.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Rain	High 80°F27°C	Low 66°F19°C	Precip 0.84 in21.3 mm97%	Cloud 90%	Wind SW 6 mph10 km/h	Wednesday: Overcast and warm, with a high of 80°F27°C and morning low of 69°F21°C. Breezy from the SW at 7 to 8 mph11 to 12 km/h. 97% chance of rain throughout the day. Heavy, humid air. Wednesday Night: Overcast, with a low around 66°F19°C. Breezy from the SSW at 6 to 7 mph9 to 11 km/h. 95% chance of rain throughout the night.
Drizzle	High 78°F26°C	Low 63°F17°C	Precip 0.03 in0.8 mm12%	Cloud 54%	Wind WNW 6 mph9 km/h	Thursday: Mostly cloudy and warm, with a high of 78°F26°C and morning low of 64°F18°C. Breezy from the WNW at 7 to 8 mph11 to 13 km/h. 11% chance of drizzle in the afternoon. Thursday Night: Partly cloudy, with a low around 63°F17°C. Light wind from the WNW around 5 mph8 km/h. 12% chance of drizzle overnight.
Clear	High 75°F24°C	Low 60°F16°C	Precip 0.01 in0.2 mm3%	Cloud 39%	Wind NNW 7 mph11 km/h	Friday: Mostly cloudy and warm, with a high of 75°F24°C and morning low of 62°F17°C. Breezy from the NNW at 7 to 9 mph12 to 15 km/h. Friday Night: Mostly clear, with a low around 60°F16°C. Breezy from the NW at 6 to 7 mph10 to 12 km/h.
Clear	High 71°F22°C	Low 56°F13°C	Precip 0 in0.1 mm1%	Cloud 36%	Wind N 6 mph10 km/h	Saturday: Mostly cloudy and warm, with a high of 71°F22°C and morning low of 58°F15°C. Breezy from the N at 7 to 8 mph12 to 13 km/h. Saturday Night: Mostly clear, with a low around 56°F13°C. Light wind from the N around 5 mph9 km/h.
Clear	High 73°F23°C	Low 54°F12°C	Precip 0 in0 mm—	Cloud 33%	Wind NNE 4 mph6 km/h	Sunday: Partly cloudy and warm, with a high of 73°F23°C and morning low of 56°F13°C. Light wind from the NE around 4 mph6 km/h. Sunday Night: Mostly clear, with a low around 54°F12°C. Light wind from the NNE around 4 mph6 km/h.
Partly Cloudy	High 75°F24°C	Low 52°F11°C	Precip 0.01 in0.3 mm4%	Cloud 44%	Wind NW 4 mph6 km/h	Monday: Partly cloudy and warm, with a high of 75°F24°C and morning low of 55°F13°C. Light wind from the NW around 4 mph6 km/h. Monday Night: Partly cloudy, with a low around 52°F11°C. Light wind from the NW around 4 mph6 km/h.
Drizzle	High 73°F23°C	Low 56°F13°C	Precip 0.04 in0.9 mm10%	Cloud 81%	Wind SSE 5 mph8 km/h	Tuesday: Overcast and warm, with a high of 73°F23°C and morning low of 57°F14°C. Light wind from the SSE around 5 mph8 km/h. 10% chance of drizzle throughout the day. Tuesday Night: Mostly cloudy, with a low around 56°F13°C. Breezy from the S at 5 to 7 mph9 to 11 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	WednesdaySep 2	80°F27°C	66°F19°C	0.84 in21.3 mm· 97%	90%	Rain	SW 6 mph10 km/h
DayOvercast and warm, with a high of 80°F27°C and morning low of 69°F21°C. Breezy from the SW at 7 to 8 mph11 to 12 km/h. 97% chance of rain throughout the day. Heavy, humid air. NightOvercast, with a low around 66°F19°C. Breezy from the SSW at 6 to 7 mph9 to 11 km/h. 95% chance of rain throughout the night.
	ThursdaySep 3	78°F26°C	63°F17°C	0.03 in0.8 mm· 12%	54%	Drizzle	WNW 6 mph9 km/h
DayMostly cloudy and warm, with a high of 78°F26°C and morning low of 64°F18°C. Breezy from the WNW at 7 to 8 mph11 to 13 km/h. 11% chance of drizzle in the afternoon. NightPartly cloudy, with a low around 63°F17°C. Light wind from the WNW around 5 mph8 km/h. 12% chance of drizzle overnight.
	FridaySep 4	75°F24°C	60°F16°C	0.01 in0.2 mm· 3%	39%	Clear	NNW 7 mph11 km/h
DayMostly cloudy and warm, with a high of 75°F24°C and morning low of 62°F17°C. Breezy from the NNW at 7 to 9 mph12 to 15 km/h. NightMostly clear, with a low around 60°F16°C. Breezy from the NW at 6 to 7 mph10 to 12 km/h.
	SaturdaySep 5	71°F22°C	56°F13°C	0 in0.1 mm· 1%	36%	Clear	N 6 mph10 km/h
DayMostly cloudy and warm, with a high of 71°F22°C and morning low of 58°F15°C. Breezy from the N at 7 to 8 mph12 to 13 km/h. NightMostly clear, with a low around 56°F13°C. Light wind from the N around 5 mph9 km/h.
	SundaySep 6	73°F23°C	54°F12°C	0 in0 mm· —	33%	Clear	NNE 4 mph6 km/h
DayPartly cloudy and warm, with a high of 73°F23°C and morning low of 56°F13°C. Light wind from the NE around 4 mph6 km/h. NightMostly clear, with a low around 54°F12°C. Light wind from the NNE around 4 mph6 km/h.
	MondaySep 7	75°F24°C	52°F11°C	0.01 in0.3 mm· 4%	44%	Partly Cloudy	NW 4 mph6 km/h
DayPartly cloudy and warm, with a high of 75°F24°C and morning low of 55°F13°C. Light wind from the NW around 4 mph6 km/h. NightPartly cloudy, with a low around 52°F11°C. Light wind from the NW around 4 mph6 km/h.
	TuesdaySep 8	73°F23°C	56°F13°C	0.04 in0.9 mm· 10%	81%	Drizzle	SSE 5 mph8 km/h
DayOvercast and warm, with a high of 73°F23°C and morning low of 57°F14°C. Light wind from the SSE around 5 mph8 km/h. 10% chance of drizzle throughout the day. NightMostly cloudy, with a low around 56°F13°C. Breezy from the S at 5 to 7 mph9 to 11 km/h.
	WednesdaySep 9	79°F26°C	62°F17°C	0.09 in2.3 mm· 23%	68%	Drizzle	SW 8 mph13 km/h
DayMostly cloudy and warm, with a high of 79°F26°C and morning low of 64°F18°C. Breezy from the SW at 8 to 9 mph13 to 15 km/h. 23% chance of drizzle throughout the day. NightMostly cloudy, with a low around 62°F17°C. Breezy from the SW at 8 to 9 mph12 to 14 km/h. 15% chance of drizzle throughout the night.
	ThursdaySep 10	77°F25°C	65°F18°C	0.11 in2.9 mm· 30%	64%	Showers	W 9 mph14 km/h
DayMostly cloudy and warm, with a high of 77°F25°C and morning low of 68°F20°C. Breezy from the W at 9 to 10 mph15 to 16 km/h. 30% chance of light rain throughout the day. NightMostly cloudy, with a low around 65°F18°C. Breezy from the W at 8 to 9 mph13 to 14 km/h. 21% chance of showers throughout the night.
	FridaySep 11	72°F22°C	61°F16°C	0.14 in3.5 mm· 26%	62%	Showers	W 7 mph12 km/h
DayMostly cloudy and warm, with a high of 72°F22°C and morning low of 62°F16°C. Breezy from the W at 8 mph13 km/h. 26% chance of showers throughout the day. NightMostly cloudy, with a low around 61°F16°C. Breezy from the W at 7 mph11 km/h. 20% chance of showers throughout the night.
	SaturdaySep 12	72°F22°C	58°F14°C	0.19 in4.8 mm· 28%	66%	Showers	SW 8 mph12 km/h
DayMostly cloudy and warm, with a high of 72°F22°C and morning low of 59°F15°C. Breezy from the SW at 8 to 9 mph13 to 14 km/h. 28% chance of light rain throughout the day. NightMostly cloudy, with a low around 58°F14°C. Breezy from the WSW at 7 to 8 mph11 to 12 km/h. 19% chance of showers throughout the night.
	SundaySep 13	72°F22°C	60°F16°C	0.16 in4 mm· 25%	70%	Light Rain	WSW 8 mph13 km/h
DayMostly cloudy and warm, with a high of 72°F22°C and morning low of 61°F16°C. Breezy from the WSW at 9 to 10 mph14 to 15 km/h. 25% chance of light rain throughout the day. NightMostly cloudy, with a low around 60°F16°C. Breezy from the WSW at 8 mph12 km/h. 25% chance of showers throughout the night.
	MondaySep 14	70°F21°C	58°F14°C	0.09 in2.3 mm· 19%	60%	Drizzle	W 8 mph13 km/h
DayMostly cloudy and warm, with a high of 70°F21°C and morning low of 58°F15°C. Breezy from the W at 9 mph14 km/h. 19% chance of drizzle throughout the day. NightMostly cloudy, with a low around 58°F14°C. Breezy from the W at 7 to 8 mph12 to 12 km/h. 15% chance of drizzle throughout the night.
	TuesdaySep 15	71°F22°C	56°F13°C	0.1 in2.6 mm· 17%	55%	Drizzle	W 8 mph12 km/h
DayMostly cloudy and warm, with a high of 71°F22°C and morning low of 57°F14°C. Breezy from the W at 8 to 9 mph13 to 14 km/h. 17% chance of drizzle throughout the day. NightMostly cloudy, with a low around 56°F13°C. Breezy from the WSW at 7 mph11 km/h. 14% chance of drizzle throughout the night.
	WednesdaySep 16	70°F21°C	55°F13°C	0.09 in2.3 mm· 21%	50%	Drizzle	WSW 7 mph12 km/h
DayMostly cloudy and warm, with a high of 70°F21°C and morning low of 56°F14°C. Breezy from the WSW at 8 to 9 mph13 to 14 km/h. 21% chance of drizzle throughout the day. NightPartly cloudy, with a low around 55°F13°C. Breezy from the WSW at 7 mph11 km/h. 14% 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

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