< Previous Month Next Month >

St. Catharines September Weather

Averages and records for weather in St. Catharines, Ontario in the month of September.

Typical St. Catharines September Weather 1991–2020
Average daily high	22.0 °C
Average daily low	14.8 °C
Average monthly precipitation	6.7 cm
Daily chance of precipitation	30.7%

St. Catharines September Weather Records 1882–2024
Highest temperature	36.7 °C	September 3, 1953
Lowest temperature	-0.5 °C	September 30, 1991
Highest daily low	24.4 °C	September 15, 1915
Lowest daily high	6.7 °C	September 26, 1928
Hottest average high temperature	26.0 °C	1921
Coldest average high temperature	17.0 °C	1928
Most daily precipitation	7.7 cm	September 29, 1924
Most monthly precipitation	23.9 cm	1977

Note: Daily averages are a moving average which includes 14 days before and after

Day	Average (°C)		Record (°C)
Day	High	Low	High	Low
September 1	24.1	17.0	33.9	7.0
September 2	24.0	16.9	35.6	6.7
September 3	23.9	16.8	36.7	5.0
September 4	23.8	16.7	35.0	6.1
September 5	23.6	16.6	33.3	2.8
September 6	23.5	16.5	33.9	5.6
September 7	23.4	16.3	33.3	6.7
September 8	23.3	16.2	32.8	4.0
September 9	23.1	16.0	32.2	6.1
September 10	23.0	15.8	34.4	5.0
September 11	22.8	15.6	33.9	2.8
September 12	22.6	15.4	35.0	2.2
September 13	22.5	15.3	36.1	5.6
September 14	22.3	15.2	34.4	2.2
September 15	22.1	14.9	33.9	3.9
September 16	21.9	14.7	32.8	3.3
September 17	21.7	14.5	31.7	4.4
September 18	21.5	14.3	31.1	3.3
September 19	21.3	14.2	31.1	2.8
September 20	21.2	14.0	30.6	2.2
September 21	20.9	13.8	30.7	1.7
September 22	20.6	13.5	31.1	0.0
September 23	20.5	13.3	32.8	1.1
September 24	20.3	13.1	31.1	1.7
September 25	20.2	12.9	31.1	2.0
September 26	20.0	12.8	30.0	1.7
September 27	19.8	12.6	30.6	2.0
September 28	19.5	12.4	30.6	1.1
September 29	19.3	12.1	28.9	0.6
September 30	19.1	11.9	27.8	-0.5

Weather Station Details

Years	Station	Coordinates
1995–2024	Port Weller (AUT)	location
1882–1994	St Catherines	location