Current Conditions

Sarnia, Ontario

71°F22°C

Rain

Wind

SSE 8 mph13 km/h

Humidity

78%

Cloud Cover

95%

As of Tuesday, September 8, 2026 at 11:55 PM EDT

Today's Outlook

Night

Mostly cloudy, with a low around 71°F21°C. Breezy from the SW at 9 to 11 mph15 to 17 km/h. 63% chance of light rain throughout the night.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Rain	High 74°F23°C	Low 71°F21°C	Precip 0.4 in10.2 mm99%	Cloud 86%	Wind SW 10 mph16 km/h	Wednesday: Overcast and warm, with a high of 74°F23°C. Breezy from the SW at 11 to 12 mph18 to 20 km/h. 99% chance of rain throughout the day. Humid. Wednesday Night: Mostly cloudy, with a low around 71°F21°C. Breezy from the SW at 9 to 11 mph15 to 17 km/h. 63% chance of light rain throughout the night.
Partly Cloudy	High 73°F23°C	Low 62°F17°C	Precip 0 in0 mm—	Cloud 68%	Wind NNW 7 mph10 km/h	Thursday: Overcast and warm, with a high of 73°F23°C and morning low of 66°F19°C. Breezy from the N at 6 to 8 mph10 to 13 km/h. Thursday Night: Partly cloudy, with a low around 62°F17°C. Breezy from the NW at 7 to 10 mph11 to 16 km/h.
Clear	High 74°F23°C	Low 58°F14°C	Precip 0.01 in0.2 mm9%	Cloud 22%	Wind SE 5 mph7 km/h	Friday: Mostly clear and warm, with a high of 74°F23°C and morning low of 58°F15°C. Light wind from the SE around 4 mph6 km/h. Friday Night: Partly cloudy, with a low around 58°F14°C. Breezy from the SE at 6 to 8 mph9 to 12 km/h.
Drizzle	High 79°F26°C	Low 62°F17°C	Precip 0.03 in0.8 mm13%	Cloud 51%	Wind S 8 mph13 km/h	Saturday: Mostly cloudy and warm, with a high of 79°F26°C and morning low of 63°F17°C. Breezy from the S at 9 to 10 mph14 to 16 km/h. 13% chance of drizzle throughout the day. Saturday Night: Partly cloudy, with a low around 62°F17°C. Breezy from the S at 8 mph13 km/h.
Drizzle	High 73°F23°C	Low 63°F17°C	Precip 0.07 in1.8 mm16%	Cloud 46%	Wind NNW 8 mph13 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 9 mph13 to 15 km/h. 16% chance of drizzle throughout the day. Sunday Night: Partly cloudy, with a low around 63°F17°C. Breezy from the NNW at 8 to 9 mph13 to 14 km/h. 14% chance of drizzle throughout the night.
Drizzle	High 70°F21°C	Low 59°F15°C	Precip 0.02 in0.6 mm11%	Cloud 57%	Wind E 8 mph14 km/h	Monday: Mostly cloudy and warm, with a high of 70°F21°C and morning low of 59°F15°C. Breezy from the ENE at 8 mph12 km/h. 11% chance of drizzle in the afternoon. Monday Night: Partly cloudy, with a low around 59°F15°C. Breezy from the E at 9 to 11 mph15 to 18 km/h. 10% chance of drizzle.
Showers	High 80°F26°C	Low 65°F19°C	Precip 0.13 in3.2 mm30%	Cloud 67%	Wind SSW 12 mph20 km/h	Tuesday: Mostly cloudy and warm, with a high of 80°F26°C and morning low of 68°F20°C. Breezy from the SSW at 14 mph22 km/h. 20% chance of drizzle throughout the day. Tuesday Night: Mostly cloudy, with a low around 65°F19°C. Breezy from the S at 11 to 13 mph18 to 21 km/h. 30% chance of showers throughout the night.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	WednesdaySep 9	74°F23°C	71°F21°C	0.4 in10.2 mm· 99%	86%	Rain	SW 10 mph16 km/h
DayOvercast and warm, with a high of 74°F23°C. Breezy from the SW at 11 to 12 mph18 to 20 km/h. 99% chance of rain throughout the day. Humid. NightMostly cloudy, with a low around 71°F21°C. Breezy from the SW at 9 to 11 mph15 to 17 km/h. 63% chance of light rain throughout the night.
	ThursdaySep 10	73°F23°C	62°F17°C	0 in0 mm· —	68%	Partly Cloudy	NNW 7 mph10 km/h
DayOvercast and warm, with a high of 73°F23°C and morning low of 66°F19°C. Breezy from the N at 6 to 8 mph10 to 13 km/h. NightPartly cloudy, with a low around 62°F17°C. Breezy from the NW at 7 to 10 mph11 to 16 km/h.
	FridaySep 11	74°F23°C	58°F14°C	0.01 in0.2 mm· 9%	22%	Clear	SE 5 mph7 km/h
DayMostly clear and warm, with a high of 74°F23°C and morning low of 58°F15°C. Light wind from the SE around 4 mph6 km/h. NightPartly cloudy, with a low around 58°F14°C. Breezy from the SE at 6 to 8 mph9 to 12 km/h.
	SaturdaySep 12	79°F26°C	62°F17°C	0.03 in0.8 mm· 13%	51%	Drizzle	S 8 mph13 km/h
DayMostly cloudy and warm, with a high of 79°F26°C and morning low of 63°F17°C. Breezy from the S at 9 to 10 mph14 to 16 km/h. 13% chance of drizzle throughout the day. NightPartly cloudy, with a low around 62°F17°C. Breezy from the S at 8 mph13 km/h.
	SundaySep 13	73°F23°C	63°F17°C	0.07 in1.8 mm· 16%	46%	Drizzle	NNW 8 mph13 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 9 mph13 to 15 km/h. 16% chance of drizzle throughout the day. NightPartly cloudy, with a low around 63°F17°C. Breezy from the NNW at 8 to 9 mph13 to 14 km/h. 14% chance of drizzle throughout the night.
	MondaySep 14	70°F21°C	59°F15°C	0.02 in0.6 mm· 11%	57%	Drizzle	E 8 mph14 km/h
DayMostly cloudy and warm, with a high of 70°F21°C and morning low of 59°F15°C. Breezy from the ENE at 8 mph12 km/h. 11% chance of drizzle in the afternoon. NightPartly cloudy, with a low around 59°F15°C. Breezy from the E at 9 to 11 mph15 to 18 km/h. 10% chance of drizzle.
	TuesdaySep 15	80°F26°C	65°F19°C	0.13 in3.2 mm· 30%	67%	Showers	SSW 12 mph20 km/h
DayMostly cloudy and warm, with a high of 80°F26°C and morning low of 68°F20°C. Breezy from the SSW at 14 mph22 km/h. 20% chance of drizzle throughout the day. NightMostly cloudy, with a low around 65°F19°C. Breezy from the S at 11 to 13 mph18 to 21 km/h. 30% chance of showers throughout the night.
	WednesdaySep 16	73°F23°C	65°F18°C	0.2 in5.1 mm· 37%	67%	Showers	NNE 7 mph12 km/h
DayMostly cloudy and warm, with a high of 73°F23°C and morning low of 65°F18°C. Breezy from the NNE at 7 mph11 km/h. 28% chance of light rain throughout the day. NightMostly cloudy, with a low around 66°F19°C. Breezy from the NNE at 8 to 9 mph13 to 15 km/h. 37% chance of showers throughout the night.
	ThursdaySep 17	75°F24°C	65°F18°C	0.26 in6.7 mm· 30%	62%	Showers	SSW 9 mph15 km/h
DayMostly cloudy and warm, with a high of 75°F24°C and morning low of 65°F18°C. Breezy from the SSW at 10 to 11 mph16 to 17 km/h. 30% chance of showers throughout the day. NightMostly cloudy, with a low around 65°F18°C. Breezy from the S at 9 to 10 mph14 to 16 km/h. 24% chance of showers throughout the night.
	FridaySep 18	70°F21°C	62°F17°C	0.2 in5.1 mm· 29%	58%	Showers	WNW 10 mph16 km/h
DayMostly cloudy and warm, with a high of 70°F21°C and morning low of 63°F17°C. Breezy from the WNW at 10 to 11 mph17 to 17 km/h. 23% chance of showers throughout the day. NightMostly cloudy, with a low around 62°F17°C. Breezy from the WNW at 10 mph16 km/h. 29% chance of showers throughout the night.
	SaturdaySep 19	66°F19°C	58°F14°C	0.16 in4 mm· 23%	56%	Showers	NW 9 mph15 km/h
DayMostly cloudy and mild, with a high of 66°F19°C and morning low of 58°F14°C. Breezy from the NW at 9 to 10 mph15 to 16 km/h. 23% chance of showers throughout the day. NightMostly cloudy, with a low around 59°F15°C. Breezy from the NW at 9 to 10 mph15 to 15 km/h. 21% chance of showers throughout the night.
	SundaySep 20	64°F18°C	55°F13°C	0.15 in3.9 mm· 25%	58%	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 NNW at 10 mph16 km/h. 25% chance of showers throughout the day. Dry air. NightMostly cloudy, with a low around 55°F13°C. Breezy from the N at 9 mph15 km/h. 23% chance of showers throughout the night.
	MondaySep 21	65°F18°C	54°F12°C	0.11 in2.8 mm· 17%	53%	Showers	N 9 mph15 km/h
DayMostly cloudy and mild, with a high of 65°F18°C and morning low of 54°F12°C. Breezy from the NNW at 9 to 10 mph15 to 16 km/h. 17% 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.
	TuesdaySep 22	65°F18°C	54°F12°C	0.11 in2.7 mm· 18%	55%	Showers	NE 9 mph15 km/h
DayMostly cloudy and mild, with a high of 65°F18°C and morning low of 54°F12°C. Breezy from the NNE at 9 to 10 mph15 to 16 km/h. 18% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 54°F12°C. Breezy from the NE at 9 mph14 km/h. 15% chance of showers throughout the night.
	WednesdaySep 23	65°F19°C	54°F12°C	0.08 in2 mm· 15%	53%	Drizzle	E 9 mph14 km/h
DayMostly cloudy and mild, with a high of 65°F19°C and morning low of 54°F12°C. Breezy from the E at 9 mph15 km/h. 15% chance of drizzle throughout the day. Dry air. NightPartly cloudy, with a low around 54°F12°C. Breezy from the E at 9 mph14 km/h. 13% chance of drizzle 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