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Precipitation
Temperature
Wind
Temperature Unit Selection
°Celsius
°Fahrenheit
Monthly Historical Averages
Lake Rosseau, ON
Exceptional El Niño dominates this fall
Content continues below
Content continues below
September
Average Temperature
High
20°
Feels 20
Low
10°
Feels 9
Average Precipitation
11 Days
Rain amount
80.6mm
Snow amount
0cm
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
20°
16
21°
17
22°
18
19°
19
16°
20
19°
21
18°
22
18°
23
19°
24
19°
25
20°
26
20°
27
19°
28
19°
29
18°
30
Forecast
Tuesday, September 15, 2026
Day
20°
Feels 21
Wind
21 km/h S
Gust
44 km/h
Humidity
64%
P.O.P
80%
Rain
~5 mm
Night
15°
Feels 14
Wind
19 km/h S
Gust
33 km/h
Humidity
100%
P.O.P
40%
Rain
<1 mm
Historical Averages
Sep 15
High
Feels
Low
Feels
Precip Frequency
Total Daylight
Humidity
Historical Averages are based on data recorded from 2000 onwards.