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Casselman, ON
Your 2026 Fall Forecast is here!
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September
Average Temperature
High
22°
Feels 22
Low
10°
Feels 9
Average Precipitation
10 Days
Rain amount
64.6mm
Snow amount
0.1cm
Content continues below
Daily Historical Averages
September 2026
S
M
T
W
T
F
S
1
2
3
4
5
6
7
8
9
22°
10
22°
11
20°
12
24°
13
25°
14
21°
15
24°
16
20°
17
20°
18
20°
19
18°
20
17°
21
17°
22
17°
23
18°
24
25
26
27
28
29
30
Forecast
Wednesday, September 9, 2026
Day
22°
Feels 25
Wind
20 km/h S
Gust
30 km/h
Humidity
79%
P.O.P
100%
Rain
~5 mm
Night
19°
Feels 18
Wind
25 km/h SW
Gust
38 km/h
Humidity
94%
P.O.P
100%
Rain
~5 mm
Historical Averages
Sep 9
High
Feels
Low
Feels
Precip Frequency
Total Daylight
Humidity
Historical Averages are based on data recorded from 2000 onwards.