S
M
T
W
T
F
S
30
78°
38°
31
84°
42°
1
72°
41°
2
63°
46°
3
61°
38°
4
66°
37°
5
67°
37°
6
74°
41°
7
77°
44°
8
80°
43°
9
81°
45°
10
80°
46°
11
89°
42°
12
73°
45°
13
76°
42°
14
81°
45°
15
81°
45°
16
72°
39°
17
71°
37°
18
71°
42°
19
72°
40°
20
70°
42°
21
70°
37°
22
75°
42°
23
74°
36°
24
65°
34°
25
62°
33°
26
64°
33°
27
67°
39°
28
63°
32°
29
66°
35°
30
66°
38°
1
63°
36°
2
63°
30°
3
64°
33°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Klamath Falls
Klamath Falls's September 2026 forecast shows daily high temperatures ranging from 61° to 89°, with overnight lows between 30° and 46°. The average high for September is 71° with an average low of 39°. 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 Klamath Falls. See also: October | November | December.
