S
M
T
W
T
F
S
30
84°
44°
31
82°
45°
1
79°
44°
2
80°
44°
3
81°
45°
4
82°
45°
5
83°
44°
6
83°
44°
7
82°
42°
8
83°
45°
9
84°
43°
10
75°
41°
11
74°
43°
12
80°
44°
13
81°
45°
14
83°
44°
15
82°
42°
16
80°
41°
17
76°
40°
18
81°
43°
19
81°
41°
20
Hist. Avg.
76°
38°
21
Hist. Avg.
76°
38°
22
Hist. Avg.
76°
37°
23
Hist. Avg.
75°
37°
24
Hist. Avg.
75°
37°
25
Hist. Avg.
74°
36°
26
Hist. Avg.
74°
36°
27
Hist. Avg.
73°
36°
28
Hist. Avg.
73°
35°
29
Hist. Avg.
72°
35°
30
Hist. Avg.
72°
35°
1
Hist. Avg.
72°
34°
2
Hist. Avg.
71°
34°
3
Hist. Avg.
71°
34°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Klamath Falls
Klamath Falls's September 2026 forecast shows daily high temperatures ranging from 74° to 84°, with overnight lows between 40° and 45°. The average high for September is 81° with an average low of 43°. 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.
