S
M
T
W
T
F
S
30
100°
75°
31
100°
77°
1
101°
76°
2
103°
76°
3
102°
80°
4
96°
80°
5
102°
77°
6
97°
78°
7
102°
77°
8
102°
78°
9
101°
79°
10
101°
78°
11
104°
78°
12
101°
78°
13
102°
79°
14
101°
79°
15
103°
79°
16
101°
79°
17
98°
77°
18
99°
74°
19
98°
74°
20
99°
74°
21
101°
75°
22
99°
75°
23
99°
75°
24
97°
74°
25
98°
71°
26
93°
72°
27
99°
74°
28
97°
74°
29
92°
73°
30
90°
68°
1
87°
67°
2
88°
66°
3
87°
65°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Austin
Austin's September 2026 forecast shows daily high temperatures ranging from 87° to 99°, with overnight lows between 65° and 74°. The average high for September is 93° with an average low of 70°. 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 Austin. See also: October | November | December.
