S
M
T
W
T
F
S
30
88°
75°
31
87°
75°
1
88°
74°
2
89°
75°
3
90°
72°
4
88°
72°
5
90°
73°
6
87°
73°
7
87°
72°
8
86°
72°
9
89°
73°
10
89°
72°
11
90°
72°
12
90°
70°
13
89°
74°
14
89°
74°
15
87°
72°
16
88°
72°
17
89°
73°
18
88°
74°
19
87°
73°
20
86°
72°
21
85°
72°
22
87°
73°
23
86°
74°
24
Hist. Avg.
86°
72°
25
Hist. Avg.
86°
72°
26
Hist. Avg.
86°
72°
27
Hist. Avg.
86°
72°
28
Hist. Avg.
86°
72°
29
Hist. Avg.
86°
71°
30
Hist. Avg.
85°
71°
1
Hist. Avg.
85°
71°
2
Hist. Avg.
85°
71°
3
Hist. Avg.
85°
70°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in St. Augustine
St. Augustine's September 2026 forecast shows daily high temperatures ranging from 85° to 90°, with overnight lows between 70° and 75°. The average high for September is 88° with an average low of 73°. 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. Augustine. See also: October | November | December.
