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Monthly Historical Averages
Brockville, ON
Ontario's 2026 Fall Forecast is here!
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September
Average Temperature
High
21°
Feels 22
Low
11°
Feels 10
Average Precipitation
10 Days
Rain amount
52.4mm
Snow amount
0.1cm
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Daily Historical Averages
September 2026
S
M
T
W
T
F
S
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
19°
24
19°
25
21°
26
21°
27
19°
28
19°
29
21°
30
24°
Forecast
Wednesday, September 23, 2026
Day
19°
Feels 19
Wind
16 km/h NE
Gust
24 km/h
Humidity
46%
P.O.P
0%
Night
8°
Feels 5
Wind
16 km/h NE
Gust
24 km/h
Humidity
100%
P.O.P
0%
Historical Averages
Sep 23
High
Feels
Low
Feels
Precip Frequency
Total Daylight
Humidity
Historical Averages are based on data recorded from 2000 onwards.