Forecast - Environment Canada

Forecast

St. Catharines, ON (Issued: 3:30 PM EST Friday 5 December 2025)

Tonight

Mainly cloudy. Wind southwest 20 km/h gusting to 40 becoming light early this evening. Wind becoming southwest 20 after midnight. Low minus 1. Wind chill minus 5 this evening.

Sat, 6 Dec

Cloudy. 40 percent chance of flurries early in the morning. Flurries beginning in the morning and ending late in the afternoon. Risk of snow squalls late in the morning and in the afternoon. Local amount 2 to 4 cm. Wind west 20 km/h gusting to 40. High plus 2. UV index 1 or low.

Night

Cloudy. Wind west 20 km/h becoming light early in the evening. Low minus 4. Wind chill minus 8 overnight.

Sun, 7 Dec

Cloudy with 60 percent chance of flurries. High minus 1.

Night

Clearing. Low minus 8.

Mon, 8 Dec

Sunny. High minus 4.

Night

Increasing cloudiness. Low minus 7.

Tue, 9 Dec

Cloudy with 60 percent chance of flurries. High plus 1.

Night

Cloudy with 60 percent chance of flurries. Low minus 1.

Wed, 10 Dec

Cloudy with 60 percent chance of flurries. High plus 1.

Night

Cloudy with 40 percent chance of flurries. Low minus 2.

Thu, 11 Dec

Cloudy with 40 percent chance of flurries. High minus 1.

24 Hour Forecast - St. Catharines, ON

Date/Time	Temp. (°C)	Weather Conditions	LOP †	Wind (km/h)
6 December 2025
2 AM	0	Cloudy	20	SW 20
3 AM	1	Cloudy	20	SW 20
4 AM	1	Cloudy	20	SW 20
5 AM	1	Cloudy	20	SW 20
6 AM	0	Chance of flurries	40	SW 20
7 AM	0	Chance of flurries	40	W 20 gust 40
8 AM	0	Chance of flurries	40	W 20 gust 40
9 AM	0	Flurries. Risk of snow squalls	80	W 20 gust 40
10 AM	0	Flurries. Risk of snow squalls	80	W 20 gust 40
11 AM	1	Flurries. Risk of snow squalls	80	W 20 gust 40
12 PM	1	Flurries. Risk of snow squalls	80	W 20 gust 40
1 PM	2	Flurries. Risk of snow squalls	80	W 20 gust 40
2 PM	2	Flurries. Risk of snow squalls	80	W 20 gust 40
3 PM	1	Flurries. Risk of snow squalls	80	W 20 gust 40
4 PM	1	Cloudy	20	W 20
5 PM	1	Cloudy	20	W 20
6 PM	1	Cloudy	20	W 20
7 PM	1	Cloudy	20	SW 15
8 PM	1	Cloudy	20	SW 15
9 PM	0	Cloudy	20	SW 15
10 PM	0	Cloudy	20	W 10
11 PM	-1	Cloudy	20	W 10
7 December 2025
12 AM	-1	Cloudy	20	W 10
1 AM	-2	Cloudy	20	W 10

† Likelihood of Precipitation (LOP) as described in the public forecast as a chance of measurable precipitation for a period of time. Nil: 0% Low: 40% or below Medium: 60% or 70% High: Above 70%

Extended Forecast - Environment Canada
	Sat, 6 Dec Flurries Max: 2°C	Sun, 7 Dec Chance of flurries Max: -1°C	Mon, 8 Dec Sunny Max: -4°C	Tue, 9 Dec Chance of flurries Max: 1°C	Wed, 10 Dec Chance of flurries Max: 1°C	Thu, 11 Dec Chance of flurries Max: -1°C
Tonight Mainly cloudy Min: -1°C	Night Cloudy Min: -4°C	Night Cloudy periods Min: -8°C	Night Cloudy periods Min: -7°C	Night Chance of flurries Min: -1°C	Night Chance of flurries Min: -2°C