S
M
T
W
T
F
S
30
77°
62°
31
80°
55°
1
79°
52°
2
76°
53°
3
75°
55°
4
78°
62°
5
82°
56°
6
82°
52°
7
75°
52°
8
74°
53°
9
78°
59°
10
76°
56°
11
75°
58°
12
73°
58°
13
73°
52°
14
72°
50°
15
70°
48°
16
71°
54°
17
71°
56°
18
76°
57°
19
78°
57°
20
79°
56°
21
76°
48°
22
74°
53°
23
69°
47°
24
70°
46°
25
67°
45°
26
68°
49°
27
68°
47°
28
Hist. Avg.
68°
46°
29
Hist. Avg.
67°
46°
30
Hist. Avg.
67°
46°
1
Hist. Avg.
66°
45°
2
Hist. Avg.
66°
45°
3
Hist. Avg.
65°
44°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in St. Johns
St. Johns's September 2026 forecast shows daily high temperatures ranging from 67° to 82°, with overnight lows between 45° and 62°. The average high for September is 75° with an average low of 53°. 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. Johns. See also: October | November | December.
