S
M
T
W
T
F
S
30
78°
55°
31
81°
58°
1
84°
57°
2
81°
56°
3
81°
56°
4
80°
55°
5
82°
56°
6
82°
56°
7
85°
55°
8
84°
42°
9
74°
48°
10
77°
49°
11
78°
50°
12
80°
47°
13
80°
47°
14
81°
51°
15
81°
51°
16
80°
50°
17
81°
52°
18
81°
51°
19
80°
50°
20
81°
53°
21
82°
53°
22
81°
52°
23
78°
51°
24
78°
49°
25
76°
45°
26
72°
47°
27
75°
48°
28
77°
44°
29
74°
47°
30
75°
42°
1
75°
43°
2
74°
47°
3
75°
48°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Twin Falls
Twin Falls's September 2026 forecast shows daily high temperatures ranging from 72° to 85°, with overnight lows between 42° and 58°. The average high for September is 79° with an average low of 50°. 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 Twin Falls. See also: October | November | December.
