S
M
T
W
T
F
S
30
67°
54°
31
71°
57°
1
74°
57°
2
74°
56°
3
73°
54°
4
73°
55°
5
72°
49°
6
73°
47°
7
65°
48°
8
65°
53°
9
66°
54°
10
70°
48°
11
69°
47°
12
64°
50°
13
69°
47°
14
65°
52°
15
68°
48°
16
68°
49°
17
64°
45°
18
Hist. Avg.
64°
49°
19
Hist. Avg.
63°
49°
20
Hist. Avg.
63°
48°
21
Hist. Avg.
63°
48°
22
Hist. Avg.
62°
48°
23
Hist. Avg.
62°
47°
24
Hist. Avg.
62°
47°
25
Hist. Avg.
61°
47°
26
Hist. Avg.
61°
47°
27
Hist. Avg.
61°
46°
28
Hist. Avg.
60°
46°
29
Hist. Avg.
60°
46°
30
Hist. Avg.
59°
45°
1
Hist. Avg.
59°
45°
2
Hist. Avg.
59°
45°
3
Hist. Avg.
58°
44°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Summerside
Summerside's September 2026 forecast shows daily high temperatures ranging from 64° to 74°, with overnight lows between 45° and 57°. The average high for September is 69° with an average low of 51°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how September weather will actually feel in Summerside. See also: October | November | December.
