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14 Days
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°Fahrenheit
Monthly Historical Averages
St. Catharines, ON
Your May weather outlook is here!
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May
Average Temperature
High
19°
Feels 19
Low
9°
Feels 8
Average Precipitation
12 Days
Rain amount
75.5mm
Snow amount
0cm
Daily Historical Averages
May 2026
S
M
T
W
T
F
S
1
2
3
14°
4
18°
5
17°
6
10°
7
9°
8
9°
9
11°
10
11°
11
12°
12
12°
13
12°
14
13°
15
14°
16
14°
17
14°
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Forecast
Sunday, May 3, 2026
Day
14°
Feels 12
Wind
32 km/h SW
Gust
50 km/h
Humidity
47%
P.O.P
30%
Night
9°
Feels 5
Wind
33 km/h SW
Gust
51 km/h
Humidity
81%
P.O.P
40%
Rain
<1 mm
Historical Averages
May 3
High
Feels
Low
Feels
Precip Frequency
Total Daylight
Humidity
Historical Averages are based on data recorded from 2000 onwards.