S
M
T
W
T
F
S
30
75°
55°
31
76°
54°
1
75°
55°
2
75°
54°
3
76°
55°
4
77°
54°
5
77°
54°
6
76°
57°
7
74°
55°
8
75°
53°
9
74°
54°
10
73°
51°
11
73°
50°
12
74°
51°
13
75°
57°
14
73°
51°
15
77°
56°
16
79°
58°
17
79°
59°
18
78°
55°
19
78°
48°
20
73°
48°
21
69°
55°
22
69°
54°
23
73°
56°
24
75°
55°
25
74°
46°
26
73°
44°
27
67°
46°
28
64°
45°
29
65°
44°
30
66°
45°
1
65°
44°
2
64°
41°
3
Hist. Avg.
65°
44°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in St. Johns
St. Johns's September 2026 forecast shows daily high temperatures ranging from 64° to 79°, with overnight lows between 41° and 59°. The average high for September is 73° with an average low of 52°. 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.
