S
M
T
W
T
F
S
30
83°
73°
31
82°
72°
1
82°
72°
2
83°
74°
3
83°
73°
4
84°
74°
5
83°
72°
6
82°
73°
7
84°
73°
8
83°
72°
9
82°
72°
10
83°
73°
11
84°
73°
12
83°
71°
13
82°
72°
14
82°
72°
15
84°
73°
16
82°
72°
17
83°
73°
18
82°
72°
19
83°
73°
20
82°
72°
21
83°
73°
22
83°
73°
23
83°
72°
24
82°
72°
25
Hist. Avg.
87°
75°
26
Hist. Avg.
87°
75°
27
Hist. Avg.
87°
75°
28
Hist. Avg.
88°
75°
29
Hist. Avg.
88°
75°
30
Hist. Avg.
88°
75°
1
Hist. Avg.
88°
75°
2
Hist. Avg.
88°
75°
3
Hist. Avg.
88°
75°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in San Antonio
San Antonio's September 2026 forecast shows daily high temperatures ranging from 82° to 84°, with overnight lows between 71° and 74°. The average high for September is 83° 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 San Antonio. See also: October | November | December.
