S
M
T
W
T
F
S
30
66°
46°
31
66°
45°
1
68°
50°
2
68°
54°
3
67°
56°
4
75°
56°
5
76°
53°
6
74°
46°
7
68°
45°
8
66°
45°
9
69°
44°
10
65°
46°
11
66°
47°
12
64°
44°
13
69°
50°
14
71°
51°
15
71°
49°
16
64°
50°
17
63°
49°
18
65°
48°
19
67°
42°
20
63°
43°
21
67°
40°
22
66°
39°
23
61°
40°
24
61°
40°
25
62°
44°
26
60°
39°
27
60°
41°
28
59°
42°
29
57°
37°
30
58°
38°
1
58°
43°
2
64°
37°
3
60°
39°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Jacksonville
Jacksonville's September 2026 forecast shows daily high temperatures ranging from 57° to 76°, with overnight lows between 37° and 56°. The average high for September is 65° with an average low of 45°. 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 Jacksonville. See also: October | November | December.
