Current Conditions

St. Catharines, Ontario

78°F26°C

Rain

Wind

SW 9 mph15 km/h

Humidity

86%

Cloud Cover

94%

As of Wednesday, September 2, 2026 at 4:48 PM EDT

Today's Outlook

Day

Overcast and warm, with a high of 79°F26°C. Breezy from the SW at 10 to 12 mph17 to 19 km/h. 40% chance of light rain in the afternoon. Heavy, humid air.

Night

Overcast, with a low around 71°F22°C. Breezy from the SW at 6 to 8 mph10 to 12 km/h. 89% chance of rain throughout the night.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Rain	High 79°F26°C	Low 71°F22°C	Precip 0.43 in10.8 mm89%	Cloud 93%	Wind SW 8 mph13 km/h	Wednesday: Overcast and warm, with a high of 79°F26°C. Breezy from the SW at 10 to 12 mph17 to 19 km/h. 40% chance of light rain in the afternoon. Heavy, humid air. Wednesday Night: Overcast, with a low around 71°F22°C. Breezy from the SW at 6 to 8 mph10 to 12 km/h. 89% chance of rain throughout the night.
Rain	High 78°F26°C	Low 70°F21°C	Precip 0.39 in9.8 mm64%	Cloud 80%	Wind WSW 6 mph9 km/h	Thursday: Mostly cloudy and warm, with a high of 78°F26°C and morning low of 70°F21°C. Light wind from the WSW around 5 mph8 km/h. 64% chance of light rain throughout the day. Heavy, humid air. Thursday Night: Overcast, with a low around 70°F21°C. Breezy from the WSW at 6 to 8 mph10 to 12 km/h. 59% chance of rain throughout the night.
Rain	High 75°F24°C	Low 69°F20°C	Precip 0.17 in4.3 mm73%	Cloud 68%	Wind NNW 5 mph8 km/h	Friday: Overcast and warm, with a high of 75°F24°C and morning low of 69°F20°C. Light wind from the NNW around 4 mph6 km/h. 19% chance of drizzle in the afternoon. Friday Night: Mostly cloudy, with a low around 69°F21°C. Breezy from the NNW at 6 to 8 mph10 to 13 km/h. 73% chance of rain throughout the night.
Clear	High 73°F23°C	Low 66°F19°C	Precip 0 in0 mm—	Cloud 23%	Wind NNE 7 mph12 km/h	Saturday: Mostly clear and warm, with a high of 73°F23°C and morning low of 66°F19°C. Breezy from the NNE at 7 to 8 mph12 to 13 km/h. Saturday Night: Mostly clear, with a low around 66°F19°C. Breezy from the NNE at 7 to 8 mph12 to 13 km/h.
Drizzle	High 72°F22°C	Low 65°F18°C	Precip 0.01 in0.3 mm13%	Cloud 23%	Wind ENE 7 mph12 km/h	Sunday: Partly cloudy and warm, with a high of 72°F22°C and morning low of 65°F18°C. Breezy from the NE at 8 to 9 mph13 to 14 km/h. 13% chance of drizzle around midday. Sunday Night: Mostly clear, with a low around 65°F18°C. Breezy from the ENE at 6 to 7 mph10 to 11 km/h.
Clear	High 75°F24°C	Low 62°F17°C	Precip 0 in0 mm—	Cloud 37%	Wind ENE 4 mph7 km/h	Monday: Partly cloudy and warm, with a high of 75°F24°C and morning low of 64°F18°C. Light wind from the ENE around 4 mph7 km/h. Monday Night: Partly cloudy, with a low around 62°F17°C. Light wind from the E around 5 mph7 km/h.
Partly Cloudy	High 75°F24°C	Low 65°F18°C	Precip 0.01 in0.2 mm4%	Cloud 71%	Wind ESE 6 mph10 km/h	Tuesday: Mostly cloudy and warm, with a high of 75°F24°C and morning low of 65°F18°C. Light wind from the ESE around 6 mph10 km/h. Tuesday Night: Mostly cloudy, with a low around 65°F18°C. Breezy from the ESE at 6 to 8 mph10 to 12 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	WednesdaySep 2	79°F26°C	71°F22°C	0.43 in10.8 mm· 89%	93%	Rain	SW 8 mph13 km/h
DayOvercast and warm, with a high of 79°F26°C. Breezy from the SW at 10 to 12 mph17 to 19 km/h. 40% chance of light rain in the afternoon. Heavy, humid air. NightOvercast, with a low around 71°F22°C. Breezy from the SW at 6 to 8 mph10 to 12 km/h. 89% chance of rain throughout the night.
	ThursdaySep 3	78°F26°C	70°F21°C	0.39 in9.8 mm· 64%	80%	Rain	WSW 6 mph9 km/h
DayMostly cloudy and warm, with a high of 78°F26°C and morning low of 70°F21°C. Light wind from the WSW around 5 mph8 km/h. 64% chance of light rain throughout the day. Heavy, humid air. NightOvercast, with a low around 70°F21°C. Breezy from the WSW at 6 to 8 mph10 to 12 km/h. 59% chance of rain throughout the night.
	FridaySep 4	75°F24°C	69°F20°C	0.17 in4.3 mm· 73%	68%	Rain	NNW 5 mph8 km/h
DayOvercast and warm, with a high of 75°F24°C and morning low of 69°F20°C. Light wind from the NNW around 4 mph6 km/h. 19% chance of drizzle in the afternoon. NightMostly cloudy, with a low around 69°F21°C. Breezy from the NNW at 6 to 8 mph10 to 13 km/h. 73% chance of rain throughout the night.
	SaturdaySep 5	73°F23°C	66°F19°C	0 in0 mm· —	23%	Clear	NNE 7 mph12 km/h
DayMostly clear and warm, with a high of 73°F23°C and morning low of 66°F19°C. Breezy from the NNE at 7 to 8 mph12 to 13 km/h. NightMostly clear, with a low around 66°F19°C. Breezy from the NNE at 7 to 8 mph12 to 13 km/h.
	SundaySep 6	72°F22°C	65°F18°C	0.01 in0.3 mm· 13%	23%	Drizzle	ENE 7 mph12 km/h
DayPartly cloudy and warm, with a high of 72°F22°C and morning low of 65°F18°C. Breezy from the NE at 8 to 9 mph13 to 14 km/h. 13% chance of drizzle around midday. NightMostly clear, with a low around 65°F18°C. Breezy from the ENE at 6 to 7 mph10 to 11 km/h.
	MondaySep 7	75°F24°C	62°F17°C	0 in0 mm· —	37%	Clear	ENE 4 mph7 km/h
DayPartly cloudy and warm, with a high of 75°F24°C and morning low of 64°F18°C. Light wind from the ENE around 4 mph7 km/h. NightPartly cloudy, with a low around 62°F17°C. Light wind from the E around 5 mph7 km/h.
	TuesdaySep 8	75°F24°C	65°F18°C	0.01 in0.2 mm· 4%	71%	Partly Cloudy	ESE 6 mph10 km/h
DayMostly cloudy and warm, with a high of 75°F24°C and morning low of 65°F18°C. Light wind from the ESE around 6 mph10 km/h. NightMostly cloudy, with a low around 65°F18°C. Breezy from the ESE at 6 to 8 mph10 to 12 km/h.
	WednesdaySep 9	79°F26°C	71°F21°C	0.07 in1.8 mm· 24%	65%	Drizzle	SW 12 mph19 km/h
DayMostly cloudy and warm, with a high of 79°F26°C and morning low of 72°F22°C. Breezy from the SW at 13 to 14 mph21 to 23 km/h. 15% chance of drizzle throughout the day. Humid. NightMostly cloudy, with a low around 71°F21°C. Breezy from the SW at 11 to 12 mph17 to 20 km/h. 24% chance of drizzle throughout the night.
	ThursdaySep 10	76°F24°C	69°F21°C	0.19 in4.9 mm· 30%	60%	Showers	WSW 11 mph18 km/h
DayMostly cloudy and warm, with a high of 76°F24°C. Breezy from the WSW at 12 mph19 km/h. 30% chance of showers throughout the day. Humid. NightMostly cloudy, with a low around 69°F21°C. Breezy from the W at 11 to 12 mph17 to 19 km/h. 28% chance of showers throughout the night.
	FridaySep 11	72°F22°C	65°F18°C	0.09 in2.4 mm· 19%	52%	Drizzle	WNW 9 mph14 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 9 mph14 km/h. 19% chance of drizzle throughout the day. NightPartly cloudy, with a low around 65°F18°C. Breezy from the NW at 9 mph14 km/h. 15% chance of drizzle throughout the night.
	SaturdaySep 12	74°F23°C	64°F18°C	0.11 in2.7 mm· 18%	53%	Showers	SSW 8 mph13 km/h
DayMostly cloudy and warm, with a high of 74°F23°C and morning low of 64°F18°C. Breezy from the SW at 8 mph13 km/h. 18% chance of drizzle throughout the day. NightMostly cloudy, with a low around 64°F18°C. Breezy from the SSW at 8 to 9 mph13 to 14 km/h. 18% chance of showers throughout the night.
	SundaySep 13	74°F23°C	67°F20°C	0.15 in3.8 mm· 21%	58%	Showers	SW 9 mph15 km/h
DayMostly cloudy and warm, with a high of 74°F23°C and morning low of 67°F20°C. Breezy from the SW at 10 mph16 km/h. 21% chance of showers throughout the day. NightMostly cloudy, with a low around 67°F20°C. Breezy from the SSW at 9 to 10 mph15 to 15 km/h. 19% chance of showers throughout the night.
	MondaySep 14	75°F24°C	67°F19°C	0.06 in1.6 mm· 13%	47%	Drizzle	SW 9 mph15 km/h
DayMostly cloudy and warm, with a high of 75°F24°C and morning low of 67°F19°C. Breezy from the SW at 9 to 10 mph15 to 16 km/h. NightPartly cloudy, with a low around 67°F19°C. Breezy from the SW at 9 to 10 mph15 to 15 km/h. 13% chance of drizzle throughout the night.
	TuesdaySep 15	74°F23°C	67°F19°C	0.12 in3 mm· 18%	47%	Drizzle	SW 10 mph16 km/h
DayPartly cloudy and warm, with a high of 74°F23°C and morning low of 67°F19°C. Breezy from the WSW at 10 mph16 km/h. 18% chance of drizzle throughout the day. NightPartly cloudy, with a low around 67°F19°C. Breezy from the SW at 9 mph15 km/h. 15% chance of drizzle throughout the night.
	WednesdaySep 16	72°F22°C	64°F18°C	0.07 in1.9 mm· 14%	43%	Drizzle	WSW 9 mph15 km/h
DayPartly cloudy and warm, with a high of 72°F22°C and morning low of 64°F18°C. Breezy from the WSW at 9 to 10 mph15 to 16 km/h. 13% chance of drizzle throughout the day. NightPartly cloudy, with a low around 64°F18°C. Breezy from the WSW at 9 mph15 km/h. 14% chance of drizzle throughout the night.

Nearby Cities

Thorold4 mi7 km Niagara-on-the-Lake10 mi16 km Niagara Falls10 mi16 km Welland13 mi21 km Grimsby16 mi26 km Port Colborne19 mi30 km

About This Forecast

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Coordinates: 43.1713°N, 79.2427°W·Elevation: 102m·Timezone: America/Toronto·Population: 136,803