Current Conditions

St. Thomas, Ontario

67°F20°C

Partly Cloudy

Wind

NNW 4 mph7 km/h

Humidity

92%

Cloud Cover

76%

As of Thursday, August 13, 2026 at 7:11 AM EDT

Today's Outlook

Day

Overcast and warm, with a high of 80°F26°C and morning low of 67°F20°C. Breezy from the NW at 5 to 7 mph9 to 11 km/h.

Night

Mostly cloudy, with a low around 66°F19°C. Light wind from the NW around 5 mph8 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Partly Cloudy	High 80°F26°C	Low 66°F19°C	Precip 0 in0 mm—	Cloud 69%	Wind NW 5 mph8 km/h	Thursday: Overcast and warm, with a high of 80°F26°C and morning low of 67°F20°C. Breezy from the NW at 5 to 7 mph9 to 11 km/h. Thursday Night: Mostly cloudy, with a low around 66°F19°C. Light wind from the NW around 5 mph8 km/h.
Partly Cloudy	High 80°F27°C	Low 65°F19°C	Precip 0 in0.1 mm3%	Cloud 71%	Wind N 4 mph7 km/h	Friday: Overcast and warm, with a high of 80°F27°C and morning low of 67°F20°C. Light wind from the NE around 4 mph6 km/h. Friday Night: Mostly cloudy, with a low around 65°F19°C. Light wind from the N around 5 mph8 km/h.
Partly Cloudy	High 80°F26°C	Low 65°F19°C	Precip 0.01 in0.3 mm5%	Cloud 47%	Wind E 7 mph12 km/h	Saturday: Partly cloudy and warm, with a high of 80°F26°C and morning low of 67°F20°C. Breezy from the E at 7 to 8 mph12 to 13 km/h. Saturday Night: Partly cloudy, with a low around 65°F19°C. Breezy from the ENE at 7 to 9 mph12 to 14 km/h.
Light Rain	High 79°F26°C	Low 69°F21°C	Precip 0.29 in7.3 mm66%	Cloud 79%	Wind SW 8 mph13 km/h	Sunday: Overcast and warm, with a high of 79°F26°C and morning low of 70°F21°C. Breezy from the SW at 8 to 10 mph14 to 16 km/h. 66% chance of light rain throughout the day. Humid. Sunday Night: Mostly cloudy, with a low around 69°F21°C. Breezy from the NE at 8 mph12 km/h. 47% chance of light rain throughout the night.
Drizzle	High 76°F24°C	Low 65°F19°C	Precip 0.05 in1.2 mm19%	Cloud 55%	Wind NW 9 mph15 km/h	Monday: Mostly cloudy and warm, with a high of 76°F24°C and morning low of 69°F20°C. Breezy from the NW at 10 to 11 mph15 to 18 km/h. 15% chance of drizzle throughout the day. Monday Night: Mostly cloudy, with a low around 65°F19°C. Breezy from the NW at 8 to 10 mph14 to 16 km/h. 19% chance of drizzle overnight.
Partly Cloudy	High 78°F25°C	Low 61°F16°C	Precip 0 in0.1 mm2%	Cloud 46%	Wind WNW 6 mph10 km/h	Tuesday: Partly cloudy and warm, with a high of 78°F25°C and morning low of 63°F17°C. Breezy from the W at 6 to 7 mph9 to 12 km/h. Tuesday Night: Partly cloudy, with a low around 61°F16°C. Light wind from the WNW around 6 mph10 km/h.
Light Rain	High 76°F24°C	Low 67°F20°C	Precip 0.18 in4.5 mm42%	Cloud 76%	Wind SW 9 mph15 km/h	Wednesday: Overcast and warm, with a high of 76°F24°C and morning low of 69°F21°C. Breezy from the SW at 10 to 12 mph17 to 19 km/h. 42% chance of light rain throughout the day. Humid. Wednesday Night: Mostly cloudy, with a low around 67°F20°C. Breezy from the SW at 8 mph13 km/h. 42% chance of light rain in the evening.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	ThursdayAug 13	80°F26°C	66°F19°C	0 in0 mm· —	69%	Partly Cloudy	NW 5 mph8 km/h
DayOvercast and warm, with a high of 80°F26°C and morning low of 67°F20°C. Breezy from the NW at 5 to 7 mph9 to 11 km/h. NightMostly cloudy, with a low around 66°F19°C. Light wind from the NW around 5 mph8 km/h.
	FridayAug 14	80°F27°C	65°F19°C	0 in0.1 mm· 3%	71%	Partly Cloudy	N 4 mph7 km/h
DayOvercast and warm, with a high of 80°F27°C and morning low of 67°F20°C. Light wind from the NE around 4 mph6 km/h. NightMostly cloudy, with a low around 65°F19°C. Light wind from the N around 5 mph8 km/h.
	SaturdayAug 15	80°F26°C	65°F19°C	0.01 in0.3 mm· 5%	47%	Partly Cloudy	E 7 mph12 km/h
DayPartly cloudy and warm, with a high of 80°F26°C and morning low of 67°F20°C. Breezy from the E at 7 to 8 mph12 to 13 km/h. NightPartly cloudy, with a low around 65°F19°C. Breezy from the ENE at 7 to 9 mph12 to 14 km/h.
	SundayAug 16	79°F26°C	69°F21°C	0.29 in7.3 mm· 66%	79%	Light Rain	SW 8 mph13 km/h
DayOvercast and warm, with a high of 79°F26°C and morning low of 70°F21°C. Breezy from the SW at 8 to 10 mph14 to 16 km/h. 66% chance of light rain throughout the day. Humid. NightMostly cloudy, with a low around 69°F21°C. Breezy from the NE at 8 mph12 km/h. 47% chance of light rain throughout the night.
	MondayAug 17	76°F24°C	65°F19°C	0.05 in1.2 mm· 19%	55%	Drizzle	NW 9 mph15 km/h
DayMostly cloudy and warm, with a high of 76°F24°C and morning low of 69°F20°C. Breezy from the NW at 10 to 11 mph15 to 18 km/h. 15% chance of drizzle throughout the day. NightMostly cloudy, with a low around 65°F19°C. Breezy from the NW at 8 to 10 mph14 to 16 km/h. 19% chance of drizzle overnight.
	TuesdayAug 18	78°F25°C	61°F16°C	0 in0.1 mm· 2%	46%	Partly Cloudy	WNW 6 mph10 km/h
DayPartly cloudy and warm, with a high of 78°F25°C and morning low of 63°F17°C. Breezy from the W at 6 to 7 mph9 to 12 km/h. NightPartly cloudy, with a low around 61°F16°C. Light wind from the WNW around 6 mph10 km/h.
	WednesdayAug 19	76°F24°C	67°F20°C	0.18 in4.5 mm· 42%	76%	Light Rain	SW 9 mph15 km/h
DayOvercast and warm, with a high of 76°F24°C and morning low of 69°F21°C. Breezy from the SW at 10 to 12 mph17 to 19 km/h. 42% chance of light rain throughout the day. Humid. NightMostly cloudy, with a low around 67°F20°C. Breezy from the SW at 8 mph13 km/h. 42% chance of light rain in the evening.
	ThursdayAug 20	74°F24°C	65°F18°C	0.16 in4 mm· 34%	54%	Showers	NW 9 mph15 km/h
DayMostly cloudy and warm, with a high of 74°F24°C and morning low of 66°F19°C. Breezy from the WNW at 10 mph15 km/h. 21% chance of drizzle throughout the day. NightMostly cloudy, with a low around 65°F18°C. Breezy from the NW at 9 mph14 km/h. 34% chance of showers throughout the night.
	FridayAug 21	74°F23°C	61°F16°C	0.07 in1.9 mm· 15%	44%	Drizzle	NW 7 mph11 km/h
DayMostly cloudy and warm, with a high of 74°F23°C and morning low of 62°F17°C. Breezy from the WNW at 7 to 8 mph12 to 12 km/h. 15% chance of drizzle throughout the day. NightPartly cloudy, with a low around 61°F16°C. Breezy from the NNW at 7 to 8 mph11 to 12 km/h. 10% chance of drizzle throughout the night.
	SaturdayAug 22	76°F25°C	62°F17°C	0.05 in1.3 mm· 17%	39%	Drizzle	WNW 7 mph11 km/h
DayPartly cloudy and warm, with a high of 76°F25°C and morning low of 63°F17°C. Breezy from the W at 7 to 8 mph12 to 13 km/h. 17% chance of drizzle in the afternoon. NightPartly cloudy, with a low around 62°F17°C. Breezy from the NW at 6 to 7 mph10 to 11 km/h. 12% chance of drizzle overnight.
	SundayAug 23	76°F25°C	62°F17°C	0.06 in1.4 mm· 14%	41%	Drizzle	W 7 mph11 km/h
DayPartly cloudy and warm, with a high of 76°F25°C and morning low of 64°F18°C. Breezy from the W at 8 mph12 km/h. 14% chance of drizzle throughout the day. NightPartly cloudy, with a low around 62°F17°C. Breezy from the WNW at 7 mph11 km/h. 11% chance of drizzle throughout the night.
	MondayAug 24	76°F24°C	63°F17°C	0.06 in1.4 mm· 12%	42%	Drizzle	W 8 mph12 km/h
DayPartly cloudy and warm, with a high of 76°F24°C and morning low of 65°F18°C. Breezy from the W at 8 to 9 mph13 to 15 km/h. 12% chance of drizzle throughout the day. NightPartly cloudy, with a low around 63°F17°C. Breezy from the WNW at 7 mph12 km/h. 11% chance of drizzle throughout the night.
	TuesdayAug 25	77°F25°C	64°F18°C	0.05 in1.2 mm· 14%	40%	Drizzle	W 8 mph12 km/h
DayPartly cloudy and warm, with a high of 77°F25°C and morning low of 65°F18°C. Breezy from the W at 8 to 9 mph13 to 15 km/h. 14% chance of drizzle throughout the day. NightPartly cloudy, with a low around 64°F18°C. Breezy from the WNW at 7 to 8 mph12 to 12 km/h. 13% chance of drizzle throughout the night.
	WednesdayAug 26	77°F25°C	64°F18°C	0.05 in1.2 mm· 16%	41%	Drizzle	WNW 7 mph12 km/h
DayPartly cloudy and warm, with a high of 77°F25°C and morning low of 65°F18°C. Breezy from the WNW at 8 to 9 mph13 to 14 km/h. 16% chance of drizzle throughout the day. NightPartly cloudy, with a low around 64°F18°C. Breezy from the NW at 7 mph11 km/h. 11% chance of drizzle throughout the night.
	ThursdayAug 27	76°F24°C	63°F17°C	0.06 in1.5 mm· 21%	46%	Drizzle	WNW 7 mph12 km/h
DayMostly cloudy and warm, with a high of 76°F24°C and morning low of 64°F18°C. Breezy from the W at 7 to 8 mph12 to 13 km/h. 21% chance of drizzle throughout the day. NightPartly cloudy, with a low around 63°F17°C. Breezy from the NNW at 7 mph11 km/h. 11% chance of drizzle throughout the night.

Nearby Cities

London15 mi24 km Tillsonburg24 mi38 km Strathroy26 mi41 km Woodstock33 mi53 km Norfolk County41 mi65 km Stratford43 mi69 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: 42.7736°N, 81.1804°W·Elevation: 232m·Timezone: America/Toronto·Population: 38,909