Current Conditions

Sarnia, Ontario

76°F25°C

Rain

Wind

NE 5 mph8 km/h

Humidity

86%

Cloud Cover

83%

As of Wednesday, September 2, 2026 at 8:19 PM EDT

Today's Outlook

Night

Mostly cloudy, with a low around 74°F23°C. Light wind from the E around 5 mph8 km/h. 93% chance of rain throughout the night.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Rain	High 88°F31°CFeels 95°F35°C	Low 74°F23°C	Precip 0.46 in11.8 mm93%	Cloud 83%	Wind SW 6 mph10 km/h	Wednesday: Overcast and hot, with a high of 88°F31°C — feels like 95°F35°C. Breezy from the WSW at 7 to 8 mph12 to 12 km/h. 84% chance of rain throughout the day. Heat risk in the afternoon. Wednesday Night: Mostly cloudy, with a low around 74°F23°C. Light wind from the E around 5 mph8 km/h. 93% chance of rain throughout the night.
Rain	High 81°F27°C	Low 71°F22°C	Precip 0.39 in9.9 mm81%	Cloud 72%	Wind W 4 mph7 km/h	Thursday: Overcast and warm, with a high of 81°F27°C and morning low of 71°F22°C. Light wind from the WNW around 4 mph7 km/h. 71% chance of rain throughout the day. Heavy, humid air. Thursday Night: Mostly cloudy, with a low around 71°F22°C. Light wind from the W around 5 mph8 km/h. 81% chance of showers throughout the night.
Rain	High 76°F24°C	Low 70°F21°C	Precip 0.3 in7.7 mm64%	Cloud 81%	Wind N 6 mph9 km/h	Friday: Overcast and warm, with a high of 76°F24°C and morning low of 70°F21°C. Breezy from the N at 5 to 8 mph9 to 12 km/h. 45% chance of light rain throughout the day. Humid. Friday Night: Mostly cloudy, with a low around 70°F21°C. Breezy from the N at 6 to 8 mph10 to 13 km/h. 64% chance of rain throughout the night.
Clear	High 75°F24°C	Low 67°F19°C	Precip 0.01 in0.2 mm9%	Cloud 22%	Wind NNE 9 mph14 km/h	Saturday: Mostly clear and warm, with a high of 75°F24°C and morning low of 67°F19°C. Breezy from the NNE at 9 to 11 mph14 to 18 km/h. Saturday Night: Mostly clear, with a low around 67°F19°C. Breezy from the NNE at 9 to 11 mph14 to 17 km/h.
Clear	High 76°F24°C	Low 64°F18°C	Precip 0 in0.1 mm2%	Cloud 34%	Wind ENE 6 mph10 km/h	Sunday: Partly cloudy and warm, with a high of 76°F24°C and morning low of 64°F18°C. Light wind from the ENE around 6 mph10 km/h. Sunday Night: Partly cloudy, with a low around 64°F18°C. Breezy from the ENE at 6 to 7 mph10 to 11 km/h.
Partly Cloudy	High 77°F25°C	Low 63°F17°C	Precip 0 in0.1 mm2%	Cloud 44%	Wind E 6 mph9 km/h	Monday: Partly cloudy and warm, with a high of 77°F25°C and morning low of 64°F18°C. Light wind from the E around 5 mph8 km/h. Monday Night: Mostly cloudy, with a low around 63°F17°C. Light wind from the E around 6 mph9 km/h.
Partly Cloudy	High 79°F26°C	Low 65°F18°C	Precip 0.01 in0.2 mm5%	Cloud 70%	Wind SSE 8 mph12 km/h	Tuesday: Mostly cloudy and warm, with a high of 79°F26°C and morning low of 65°F18°C. Breezy from the SSE at 7 to 9 mph12 to 14 km/h. Tuesday Night: Mostly cloudy, with a low around 65°F18°C. Breezy from the SSE at 8 to 10 mph13 to 16 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	WednesdaySep 2	88°F31°C Feels 95°F35°C	74°F23°C	0.46 in11.8 mm· 93%	83%	Rain	SW 6 mph10 km/h
DayOvercast and hot, with a high of 88°F31°C — feels like 95°F35°C. Breezy from the WSW at 7 to 8 mph12 to 12 km/h. 84% chance of rain throughout the day. Heat risk in the afternoon. NightMostly cloudy, with a low around 74°F23°C. Light wind from the E around 5 mph8 km/h. 93% chance of rain throughout the night.
	ThursdaySep 3	81°F27°C	71°F22°C	0.39 in9.9 mm· 81%	72%	Rain	W 4 mph7 km/h
DayOvercast and warm, with a high of 81°F27°C and morning low of 71°F22°C. Light wind from the WNW around 4 mph7 km/h. 71% chance of rain throughout the day. Heavy, humid air. NightMostly cloudy, with a low around 71°F22°C. Light wind from the W around 5 mph8 km/h. 81% chance of showers throughout the night.
	FridaySep 4	76°F24°C	70°F21°C	0.3 in7.7 mm· 64%	81%	Rain	N 6 mph9 km/h
DayOvercast and warm, with a high of 76°F24°C and morning low of 70°F21°C. Breezy from the N at 5 to 8 mph9 to 12 km/h. 45% chance of light rain throughout the day. Humid. NightMostly cloudy, with a low around 70°F21°C. Breezy from the N at 6 to 8 mph10 to 13 km/h. 64% chance of rain throughout the night.
	SaturdaySep 5	75°F24°C	67°F19°C	0.01 in0.2 mm· 9%	22%	Clear	NNE 9 mph14 km/h
DayMostly clear and warm, with a high of 75°F24°C and morning low of 67°F19°C. Breezy from the NNE at 9 to 11 mph14 to 18 km/h. NightMostly clear, with a low around 67°F19°C. Breezy from the NNE at 9 to 11 mph14 to 17 km/h.
	SundaySep 6	76°F24°C	64°F18°C	0 in0.1 mm· 2%	34%	Clear	ENE 6 mph10 km/h
DayPartly cloudy and warm, with a high of 76°F24°C and morning low of 64°F18°C. Light wind from the ENE around 6 mph10 km/h. NightPartly cloudy, with a low around 64°F18°C. Breezy from the ENE at 6 to 7 mph10 to 11 km/h.
	MondaySep 7	77°F25°C	63°F17°C	0 in0.1 mm· 2%	44%	Partly Cloudy	E 6 mph9 km/h
DayPartly cloudy and warm, with a high of 77°F25°C and morning low of 64°F18°C. Light wind from the E around 5 mph8 km/h. NightMostly cloudy, with a low around 63°F17°C. Light wind from the E around 6 mph9 km/h.
	TuesdaySep 8	79°F26°C	65°F18°C	0.01 in0.2 mm· 5%	70%	Partly Cloudy	SSE 8 mph12 km/h
DayMostly cloudy and warm, with a high of 79°F26°C and morning low of 65°F18°C. Breezy from the SSE at 7 to 9 mph12 to 14 km/h. NightMostly cloudy, with a low around 65°F18°C. Breezy from the SSE at 8 to 10 mph13 to 16 km/h.
	WednesdaySep 9	85°F30°C Feels 90°F32°C	71°F22°C	0.1 in2.6 mm· 23%	57%	Drizzle	SW 11 mph17 km/h
DayMostly cloudy and warm, with a high of 85°F30°C and morning low of 72°F22°C. Breezy from the SW at 11 to 12 mph18 to 19 km/h. 23% chance of drizzle throughout the day. Humid. NightMostly cloudy, with a low around 71°F22°C. Breezy from the SW at 10 mph16 km/h. 21% chance of drizzle throughout the night.
	ThursdaySep 10	77°F25°C	69°F21°C	0.18 in4.6 mm· 34%	59%	Showers	WNW 10 mph16 km/h
DayMostly cloudy and warm, with a high of 77°F25°C and morning low of 71°F22°C. Breezy from the WNW at 10 mph16 km/h. 34% chance of showers throughout the day. Humid. NightMostly cloudy, with a low around 69°F21°C. Breezy from the WNW at 9 to 10 mph15 to 17 km/h. 25% chance of showers throughout the night.
	FridaySep 11	75°F24°C	65°F18°C	0.13 in3.2 mm· 17%	49%	Showers	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 mph14 km/h. 17% chance of showers throughout the day. NightPartly cloudy, with a low around 65°F19°C. Breezy from the NW at 8 mph13 km/h. 14% chance of showers throughout the night.
	SaturdaySep 12	77°F25°C	65°F18°C	0.1 in2.6 mm· 18%	51%	Drizzle	SSW 9 mph15 km/h
DayMostly cloudy and warm, with a high of 77°F25°C and morning low of 65°F18°C. Breezy from the SSW at 10 mph16 km/h. 18% chance of drizzle throughout the day. NightPartly cloudy, with a low around 65°F18°C. Breezy from the SSW at 9 mph14 km/h. 15% chance of drizzle throughout the night.
	SundaySep 13	77°F25°C	67°F19°C	0.14 in3.6 mm· 22%	56%	Showers	SSW 9 mph15 km/h
DayMostly cloudy and warm, with a high of 77°F25°C and morning low of 67°F19°C. Breezy from the SW at 10 mph16 km/h. 22% chance of showers throughout the day. NightMostly cloudy, with a low around 67°F19°C. Breezy from the SSW at 9 to 10 mph15 to 15 km/h. 20% chance of drizzle throughout the night.
	MondaySep 14	76°F24°C	66°F19°C	0.08 in2.1 mm· 18%	54%	Drizzle	SW 9 mph15 km/h
DayMostly cloudy and warm, with a high of 76°F24°C and morning low of 66°F19°C. Breezy from the SW at 10 mph16 km/h. 18% chance of drizzle throughout the day. NightMostly cloudy, with a low around 67°F19°C. Breezy from the SSW at 9 mph15 km/h. 17% chance of drizzle throughout the night.
	TuesdaySep 15	75°F24°C	65°F18°C	0.08 in2.1 mm· 15%	47%	Drizzle	SSW 9 mph15 km/h
DayPartly cloudy and warm, with a high of 75°F24°C and morning low of 65°F18°C. Breezy from the SW at 10 mph16 km/h. 14% chance of drizzle throughout the day. NightPartly cloudy, with a low around 65°F18°C. Breezy from the SSW at 9 mph14 km/h. 15% chance of drizzle throughout the night.
	WednesdaySep 16	74°F23°C	64°F18°C	0.11 in2.8 mm· 22%	42%	Showers	SW 9 mph14 km/h
DayPartly cloudy and warm, with a high of 74°F23°C and morning low of 64°F18°C. Breezy from the SW at 9 to 10 mph15 to 15 km/h. 22% chance of showers throughout the day. NightPartly cloudy, with a low around 64°F18°C. Breezy from the SW at 9 mph14 km/h. 22% 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