Current Conditions

St. Catharines, Ontario

56°F13°C

Clear

Wind

ENE 12 mph20 km/h

Humidity

82%

Cloud Cover

21%

As of Wednesday, September 23, 2026 at 2:40 AM EDT

Today's Outlook

Day

Mostly clear and mild, with a high of 63°F17°C and morning low of 55°F13°C. Windy from the ENE at 14 to 16 mph22 to 25 km/h. Dry air.

Night

Mostly clear, with a low around 55°F13°C. Breezy from the ENE at 13 to 14 mph20 to 22 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Clear	High 63°F17°C	Low 55°F13°C	Precip 0 in0 mm—	Cloud 21%	Wind ENE 13 mph21 km/h	Wednesday: Mostly clear and mild, with a high of 63°F17°C and morning low of 55°F13°C. Windy from the ENE at 14 to 16 mph22 to 25 km/h. Dry air. Wednesday Night: Mostly clear, with a low around 55°F13°C. Breezy from the ENE at 13 to 14 mph20 to 22 km/h.
Clear	High 63°F17°C	Low 52°F11°C	Precip 0 in0 mm—	Cloud 10%	Wind ENE 8 mph13 km/h	Thursday: Mostly clear and mild, with a high of 63°F17°C and morning low of 52°F11°C. Breezy from the ENE at 9 to 11 mph15 to 18 km/h. Dry air. Thursday Night: Mostly clear, with a low around 53°F12°C. Breezy from the E at 8 to 10 mph12 to 16 km/h.
Clear	High 66°F19°C	Low 52°F11°C	Precip 0 in0 mm—	Cloud 26%	Wind NNE 7 mph11 km/h	Friday: Partly cloudy and mild, with a high of 66°F19°C and morning low of 53°F12°C. Breezy from the NNE at 8 to 9 mph12 to 14 km/h. Dry air. Friday Night: Mostly clear, with a low around 52°F11°C. Breezy from the N at 6 to 9 mph10 to 14 km/h.
Clear	High 68°F20°C	Low 56°F13°C	Precip 0 in0 mm—	Cloud 32%	Wind N 9 mph14 km/h	Saturday: Partly cloudy and warm, with a high of 68°F20°C and morning low of 56°F13°C. Breezy from the NNE at 9 mph14 km/h. Saturday Night: Partly cloudy, with a low around 56°F14°C. Breezy from the N at 9 to 10 mph14 to 16 km/h.
Drizzle	High 65°F18°C	Low 58°F15°C	Precip 0.03 in0.8 mm20%	Cloud 70%	Wind NNE 10 mph15 km/h	Sunday: Mostly cloudy and mild, with a high of 65°F18°C and morning low of 58°F15°C. Breezy from the NNE at 10 to 12 mph16 to 19 km/h. 18% chance of drizzle in the afternoon. Sunday Night: Mostly cloudy, with a low around 58°F15°C. Breezy from the NNE at 9 to 10 mph14 to 17 km/h. 20% chance of drizzle in the evening.
Drizzle	High 64°F18°C	Low 59°F15°C	Precip 0.03 in0.8 mm19%	Cloud 67%	Wind NNE 6 mph10 km/h	Monday: Mostly cloudy and mild, with a high of 64°F18°C and morning low of 59°F15°C. Breezy from the N at 6 to 7 mph10 to 12 km/h. 18% chance of drizzle in the morning. Monday Night: Mostly cloudy, with a low around 59°F15°C. Breezy from the NNE at 6 to 7 mph9 to 12 km/h. 19% chance of drizzle overnight.
Partly Cloudy	High 67°F20°C	Low 58°F14°C	Precip 0 in0.1 mm3%	Cloud 47%	Wind SSW 5 mph8 km/h	Tuesday: Partly cloudy and mild, with a high of 67°F20°C and morning low of 58°F14°C. Light wind from the SSW around 5 mph8 km/h. Tuesday Night: Partly cloudy, with a low around 58°F14°C. Breezy from the S at 5 to 7 mph9 to 11 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	WednesdaySep 23	63°F17°C	55°F13°C	0 in0 mm· —	21%	Clear	ENE 13 mph21 km/h
DayMostly clear and mild, with a high of 63°F17°C and morning low of 55°F13°C. Windy from the ENE at 14 to 16 mph22 to 25 km/h. Dry air. NightMostly clear, with a low around 55°F13°C. Breezy from the ENE at 13 to 14 mph20 to 22 km/h.
	ThursdaySep 24	63°F17°C	52°F11°C	0 in0 mm· —	10%	Clear	ENE 8 mph13 km/h
DayMostly clear and mild, with a high of 63°F17°C and morning low of 52°F11°C. Breezy from the ENE at 9 to 11 mph15 to 18 km/h. Dry air. NightMostly clear, with a low around 53°F12°C. Breezy from the E at 8 to 10 mph12 to 16 km/h.
	FridaySep 25	66°F19°C	52°F11°C	0 in0 mm· —	26%	Clear	NNE 7 mph11 km/h
DayPartly cloudy and mild, with a high of 66°F19°C and morning low of 53°F12°C. Breezy from the NNE at 8 to 9 mph12 to 14 km/h. Dry air. NightMostly clear, with a low around 52°F11°C. Breezy from the N at 6 to 9 mph10 to 14 km/h.
	SaturdaySep 26	68°F20°C	56°F13°C	0 in0 mm· —	32%	Clear	N 9 mph14 km/h
DayPartly cloudy and warm, with a high of 68°F20°C and morning low of 56°F13°C. Breezy from the NNE at 9 mph14 km/h. NightPartly cloudy, with a low around 56°F14°C. Breezy from the N at 9 to 10 mph14 to 16 km/h.
	SundaySep 27	65°F18°C	58°F15°C	0.03 in0.8 mm· 20%	70%	Drizzle	NNE 10 mph15 km/h
DayMostly cloudy and mild, with a high of 65°F18°C and morning low of 58°F15°C. Breezy from the NNE at 10 to 12 mph16 to 19 km/h. 18% chance of drizzle in the afternoon. NightMostly cloudy, with a low around 58°F15°C. Breezy from the NNE at 9 to 10 mph14 to 17 km/h. 20% chance of drizzle in the evening.
	MondaySep 28	64°F18°C	59°F15°C	0.03 in0.8 mm· 19%	67%	Drizzle	NNE 6 mph10 km/h
DayMostly cloudy and mild, with a high of 64°F18°C and morning low of 59°F15°C. Breezy from the N at 6 to 7 mph10 to 12 km/h. 18% chance of drizzle in the morning. NightMostly cloudy, with a low around 59°F15°C. Breezy from the NNE at 6 to 7 mph9 to 12 km/h. 19% chance of drizzle overnight.
	TuesdaySep 29	67°F20°C	58°F14°C	0 in0.1 mm· 3%	47%	Partly Cloudy	SSW 5 mph8 km/h
DayPartly cloudy and mild, with a high of 67°F20°C and morning low of 58°F14°C. Light wind from the SSW around 5 mph8 km/h. NightPartly cloudy, with a low around 58°F14°C. Breezy from the S at 5 to 7 mph9 to 11 km/h.
	WednesdaySep 30	69°F21°C	59°F15°C	0.09 in2.3 mm· 30%	68%	Showers	S 8 mph13 km/h
DayMostly cloudy and warm, with a high of 69°F21°C and morning low of 60°F15°C. Breezy from the S at 8 to 9 mph13 to 14 km/h. 16% chance of drizzle throughout the day. NightMostly cloudy, with a low around 59°F15°C. Breezy from the S at 8 to 10 mph13 to 16 km/h. 30% chance of showers in the evening.
	ThursdayOct 1	67°F19°C	61°F16°C	0.18 in4.5 mm· 29%	67%	Showers	SW 10 mph17 km/h
DayMostly cloudy and mild, with a high of 67°F19°C and morning low of 61°F16°C. Breezy from the SW at 11 mph17 km/h. 23% chance of showers throughout the day. NightMostly cloudy, with a low around 61°F16°C. Breezy from the SW at 10 mph16 km/h. 29% chance of showers throughout the night.
	FridayOct 2	64°F18°C	58°F14°C	0.16 in4.1 mm· 22%	64%	Showers	WSW 10 mph16 km/h
DayMostly cloudy and mild, with a high of 64°F18°C and morning low of 58°F14°C. Breezy from the WSW at 10 to 11 mph16 to 17 km/h. 21% chance of showers throughout the day. NightMostly cloudy, with a low around 59°F15°C. Breezy from the WSW at 9 to 10 mph15 to 16 km/h. 22% chance of showers throughout the night.
	SaturdayOct 3	64°F18°C	57°F14°C	0.14 in3.5 mm· 19%	65%	Showers	SW 10 mph16 km/h
DayMostly cloudy and mild, with a high of 64°F18°C and morning low of 57°F14°C. Breezy from the SW at 10 mph16 km/h. 19% chance of drizzle throughout the day. NightMostly cloudy, with a low around 57°F14°C. Breezy from the SW at 10 mph16 km/h. 19% chance of showers throughout the night.
	SundayOct 4	64°F18°C	58°F14°C	0.2 in5 mm· 27%	65%	Showers	SW 10 mph16 km/h
DayMostly cloudy and mild, with a high of 64°F18°C and morning low of 58°F14°C. Breezy from the SW at 10 mph16 km/h. 26% chance of showers throughout the day. NightMostly cloudy, with a low around 58°F15°C. Breezy from the SW at 10 to 11 mph16 to 17 km/h. 27% chance of showers throughout the night.
	MondayOct 5	61°F16°C	55°F13°C	0.15 in3.8 mm· 26%	58%	Showers	W 10 mph16 km/h
DayMostly cloudy and mild, with a high of 61°F16°C and morning low of 55°F13°C. Breezy from the W at 10 to 11 mph17 to 17 km/h. 26% chance of showers throughout the day. Dry air. NightMostly cloudy, with a low around 56°F13°C. Breezy from the W at 10 to 11 mph16 to 17 km/h. 21% chance of showers throughout the night.
	TuesdayOct 6	60°F16°C	54°F12°C	0.12 in3 mm· 22%	59%	Showers	WSW 10 mph16 km/h
DayMostly cloudy and mild, with a high of 60°F16°C and morning low of 54°F12°C. Breezy from the WSW at 10 to 11 mph17 to 18 km/h. 22% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 54°F12°C. Breezy from the W at 10 mph16 km/h. 19% chance of showers throughout the night.
	WednesdayOct 7	59°F15°C	53°F12°C	0.11 in2.9 mm· 28%	60%	Showers	W 10 mph17 km/h
DayMostly cloudy and mild, with a high of 59°F15°C and morning low of 53°F12°C. Breezy from the W at 11 mph17 km/h. 28% chance of showers throughout the day. Dry air. NightMostly cloudy, with a low around 53°F12°C. Breezy from the W at 10 to 11 mph16 to 17 km/h. 26% 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