S
M
T
W
T
F
S
30
71°
60°
31
69°
54°
1
60°
51°
2
56°
42°
3
62°
42°
4
66°
50°
5
63°
51°
6
58°
55°
7
71°
56°
8
64°
49°
9
53°
40°
10
62°
40°
11
65°
52°
12
55°
41°
13
66°
42°
14
68°
57°
15
63°
49°
16
68°
51°
17
72°
50°
18
56°
50°
19
55°
44°
20
51°
42°
21
59°
44°
22
56°
44°
23
N/A
24
65°
44°
25
65°
38°
26
57°
36°
27
59°
45°
28
51°
37°
29
55°
48°
30
56°
46°
1
65°
54°
2
66°
58°
3
65°
46°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in St. John's
St. John's's September 2026 forecast shows daily high temperatures ranging from 55° to 66°, with overnight lows between 46° and 58°. The average high for September is 61° with an average low of 50°. 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 St. John's. See also: October | November | December.
