S
M
T
W
T
F
S
30
74°
54°
31
79°
55°
1
79°
55°
2
78°
48°
3
75°
51°
4
78°
54°
5
73°
53°
6
74°
53°
7
70°
52°
8
70°
50°
9
72°
46°
10
69°
45°
11
70°
52°
12
77°
48°
13
75°
52°
14
73°
51°
15
72°
51°
16
Hist. Avg.
71°
46°
17
Hist. Avg.
70°
46°
18
Hist. Avg.
70°
46°
19
Hist. Avg.
70°
45°
20
Hist. Avg.
69°
45°
21
Hist. Avg.
69°
44°
22
Hist. Avg.
68°
44°
23
Hist. Avg.
68°
44°
24
Hist. Avg.
68°
44°
25
Hist. Avg.
67°
43°
26
Hist. Avg.
67°
43°
27
Hist. Avg.
66°
43°
28
Hist. Avg.
66°
42°
29
Hist. Avg.
66°
42°
30
Hist. Avg.
65°
42°
1
Hist. Avg.
65°
41°
2
Hist. Avg.
64°
41°
3
Hist. Avg.
64°
41°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Austin
Austin's September 2026 forecast shows daily high temperatures ranging from 69° to 79°, with overnight lows between 45° and 55°. The average high for September is 74° with an average low of 51°. 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.