Current Conditions

Sarnia, Ontario

77°F25°C

Cloudy

Wind

SSE 7 mph12 km/h

Humidity

60%

Cloud Cover

95%

As of Tuesday, September 8, 2026 at 4:16 PM EDT

Today's Outlook

Day

Overcast and warm, with a high of 77°F25°C. Breezy from the SSE at 7 mph11 km/h.

Night

Overcast, with a low around 70°F21°C. Breezy from the SSE at 9 mph14 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Cloudy	High 77°F25°C	Low 70°F21°C	Precip 0 in0 mm—	Cloud 96%	Wind SSE 8 mph12 km/h	Tuesday: Overcast and warm, with a high of 77°F25°C. Breezy from the SSE at 7 mph11 km/h. Tuesday Night: Overcast, with a low around 70°F21°C. Breezy from the SSE at 9 mph14 km/h.
Rain	High 75°F24°C	Low 71°F21°C	Precip 0.41 in10.3 mm98%	Cloud 87%	Wind SW 10 mph17 km/h	Wednesday: Overcast and warm, with a high of 75°F24°C. Breezy from the SW at 11 to 12 mph18 to 20 km/h. 98% chance of rain throughout the day. Humid. Wednesday Night: Mostly cloudy, with a low around 71°F21°C. Breezy from the SW at 10 to 11 mph15 to 18 km/h. 66% chance of light rain throughout the night.
Partly Cloudy	High 73°F23°C	Low 64°F18°C	Precip 0 in0.1 mm9%	Cloud 65%	Wind NW 6 mph10 km/h	Thursday: Overcast and warm, with a high of 73°F23°C and morning low of 65°F19°C. Breezy from the NNW at 6 to 7 mph9 to 12 km/h. Thursday Night: Partly cloudy, with a low around 64°F18°C. Breezy from the WNW at 7 to 10 mph11 to 16 km/h.
Clear	High 75°F24°C	Low 59°F15°C	Precip 0 in0 mm—	Cloud 19%	Wind SE 5 mph8 km/h	Friday: Mostly clear and warm, with a high of 75°F24°C and morning low of 59°F15°C. Light wind from the SSE around 4 mph6 km/h. Friday Night: Mostly clear, with a low around 59°F15°C. Breezy from the SE at 6 to 9 mph10 to 14 km/h.
Showers	High 79°F26°C	Low 63°F17°C	Precip 0.06 in1.5 mm21%	Cloud 51%	Wind S 9 mph15 km/h	Saturday: Mostly cloudy and warm, with a high of 79°F26°C and morning low of 65°F18°C. Breezy from the S at 10 to 11 mph16 to 18 km/h. 13% chance of drizzle throughout the day. Saturday Night: Mostly cloudy, with a low around 63°F17°C. Breezy from the S at 8 to 9 mph13 to 14 km/h. 21% chance of showers in the evening.
Drizzle	High 73°F23°C	Low 64°F18°C	Precip 0.07 in1.9 mm17%	Cloud 47%	Wind NNW 8 mph14 km/h	Sunday: Mostly cloudy and warm, with a high of 73°F23°C and morning low of 66°F19°C. Breezy from the NNW at 8 to 10 mph13 to 15 km/h. 17% chance of drizzle throughout the day. Sunday Night: Partly cloudy, with a low around 64°F18°C. Breezy from the NNW at 9 mph14 km/h. 17% chance of drizzle throughout the night.
Drizzle	High 69°F21°C	Low 59°F15°C	Precip 0.05 in1.3 mm12%	Cloud 59%	Wind NE 9 mph14 km/h	Monday: Mostly cloudy and warm, with a high of 69°F21°C and morning low of 59°F15°C. Breezy from the NE at 8 to 9 mph13 to 14 km/h. 10% chance of drizzle throughout the day. Monday Night: Mostly cloudy, with a low around 59°F15°C. Breezy from the E at 10 to 11 mph15 to 17 km/h. 12% chance of drizzle throughout the night.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	TuesdaySep 8	77°F25°C	70°F21°C	0 in0 mm· —	96%	Cloudy	SSE 8 mph12 km/h
DayOvercast and warm, with a high of 77°F25°C. Breezy from the SSE at 7 mph11 km/h. NightOvercast, with a low around 70°F21°C. Breezy from the SSE at 9 mph14 km/h.
	WednesdaySep 9	75°F24°C	71°F21°C	0.41 in10.3 mm· 98%	87%	Rain	SW 10 mph17 km/h
DayOvercast and warm, with a high of 75°F24°C. Breezy from the SW at 11 to 12 mph18 to 20 km/h. 98% chance of rain throughout the day. Humid. NightMostly cloudy, with a low around 71°F21°C. Breezy from the SW at 10 to 11 mph15 to 18 km/h. 66% chance of light rain throughout the night.
	ThursdaySep 10	73°F23°C	64°F18°C	0 in0.1 mm· 9%	65%	Partly Cloudy	NW 6 mph10 km/h
DayOvercast and warm, with a high of 73°F23°C and morning low of 65°F19°C. Breezy from the NNW at 6 to 7 mph9 to 12 km/h. NightPartly cloudy, with a low around 64°F18°C. Breezy from the WNW at 7 to 10 mph11 to 16 km/h.
	FridaySep 11	75°F24°C	59°F15°C	0 in0 mm· —	19%	Clear	SE 5 mph8 km/h
DayMostly clear and warm, with a high of 75°F24°C and morning low of 59°F15°C. Light wind from the SSE around 4 mph6 km/h. NightMostly clear, with a low around 59°F15°C. Breezy from the SE at 6 to 9 mph10 to 14 km/h.
	SaturdaySep 12	79°F26°C	63°F17°C	0.06 in1.5 mm· 21%	51%	Showers	S 9 mph15 km/h
DayMostly cloudy and warm, with a high of 79°F26°C and morning low of 65°F18°C. Breezy from the S at 10 to 11 mph16 to 18 km/h. 13% chance of drizzle throughout the day. NightMostly cloudy, with a low around 63°F17°C. Breezy from the S at 8 to 9 mph13 to 14 km/h. 21% chance of showers in the evening.
	SundaySep 13	73°F23°C	64°F18°C	0.07 in1.9 mm· 17%	47%	Drizzle	NNW 8 mph14 km/h
DayMostly cloudy and warm, with a high of 73°F23°C and morning low of 66°F19°C. Breezy from the NNW at 8 to 10 mph13 to 15 km/h. 17% chance of drizzle throughout the day. NightPartly cloudy, with a low around 64°F18°C. Breezy from the NNW at 9 mph14 km/h. 17% chance of drizzle throughout the night.
	MondaySep 14	69°F21°C	59°F15°C	0.05 in1.3 mm· 12%	59%	Drizzle	NE 9 mph14 km/h
DayMostly cloudy and warm, with a high of 69°F21°C and morning low of 59°F15°C. Breezy from the NE at 8 to 9 mph13 to 14 km/h. 10% chance of drizzle throughout the day. NightMostly cloudy, with a low around 59°F15°C. Breezy from the E at 10 to 11 mph15 to 17 km/h. 12% chance of drizzle throughout the night.
	TuesdaySep 15	77°F25°C	64°F18°C	0.15 in3.8 mm· 32%	68%	Showers	SSW 12 mph20 km/h
DayMostly cloudy and warm, with a high of 77°F25°C and morning low of 66°F19°C. Breezy from the SSW at 13 to 14 mph21 to 22 km/h. 32% chance of showers throughout the day. NightMostly cloudy, with a low around 64°F18°C. Breezy from the S at 11 to 12 mph18 to 20 km/h. 22% chance of showers throughout the night.
	WednesdaySep 16	72°F22°C	64°F18°C	0.12 in3.1 mm· 22%	65%	Showers	NNE 8 mph13 km/h
DayMostly cloudy and warm, with a high of 72°F22°C and morning low of 64°F18°C. Breezy from the N at 8 mph13 km/h. 19% chance of drizzle throughout the day. NightMostly cloudy, with a low around 65°F18°C. Breezy from the NNE at 8 to 10 mph14 to 16 km/h. 22% chance of showers throughout the night.
	ThursdaySep 17	75°F24°C	64°F18°C	0.19 in4.9 mm· 25%	64%	Showers	SSE 8 mph13 km/h
DayMostly cloudy and warm, with a high of 75°F24°C and morning low of 64°F18°C. Breezy from the S at 8 to 9 mph13 to 15 km/h. 25% chance of showers throughout the day. NightMostly cloudy, with a low around 64°F18°C. Breezy from the SSE at 8 to 10 mph14 to 16 km/h. 22% chance of showers throughout the night.
	FridaySep 18	72°F22°C	64°F18°C	0.15 in3.7 mm· 22%	59%	Showers	W 10 mph16 km/h
DayMostly cloudy and warm, with a high of 72°F22°C and morning low of 65°F18°C. Breezy from the WNW at 10 to 11 mph17 to 17 km/h. 21% chance of showers throughout the day. NightMostly cloudy, with a low around 64°F18°C. Breezy from the W at 10 mph16 km/h. 22% chance of showers throughout the night.
	SaturdaySep 19	69°F20°C	60°F16°C	0.18 in4.6 mm· 25%	58%	Showers	WNW 10 mph16 km/h
DayMostly cloudy and warm, with a high of 69°F20°C and morning low of 60°F16°C. Breezy from the WNW at 10 mph16 km/h. 21% chance of showers throughout the day. NightMostly cloudy, with a low around 61°F16°C. Breezy from the NW at 10 mph16 km/h. 25% chance of showers throughout the night.
	SundaySep 20	65°F18°C	58°F14°C	0.18 in4.6 mm· 28%	65%	Showers	N 10 mph15 km/h
DayMostly cloudy and mild, with a high of 65°F18°C and morning low of 58°F14°C. Breezy from the NNW at 10 mph16 km/h. 25% chance of drizzle throughout the day. NightMostly cloudy, with a low around 58°F14°C. Breezy from the N at 9 to 10 mph15 to 16 km/h. 28% chance of showers throughout the night.
	MondaySep 21	64°F18°C	55°F13°C	0.13 in3.3 mm· 22%	63%	Showers	N 9 mph15 km/h
DayMostly cloudy and mild, with a high of 64°F18°C and morning low of 55°F13°C. Breezy from the N at 9 to 10 mph15 to 16 km/h. 22% chance of showers throughout the day. Dry air. NightMostly cloudy, with a low around 55°F13°C. Breezy from the NNE at 9 mph14 km/h. 20% chance of showers throughout the night.
	TuesdaySep 22	64°F18°C	54°F12°C	0.13 in3.3 mm· 16%	54%	Showers	N 9 mph15 km/h
DayMostly cloudy and mild, with a high of 64°F18°C and morning low of 54°F12°C. Breezy from the N at 9 to 10 mph15 to 16 km/h. 15% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 54°F12°C. Breezy from the NNE at 9 mph14 km/h. 16% chance of showers throughout the night.

Nearby Cities

Strathroy40 mi64 km Chatham41 mi65 km Tecumseh52 mi83 km Windsor56 mi91 km London59 mi95 km LaSalle61 mi98 km

About This Forecast

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Coordinates: 42.9787°N, 82.4041°W·Elevation: 185m·Timezone: America/Toronto·Population: 72,125