S
M
T
W
T
F
S
30
81°
45°
31
81°
45°
1
76°
41°
2
71°
38°
3
72°
41°
4
79°
44°
5
80°
42°
6
69°
33°
7
68°
32°
8
70°
35°
9
76°
38°
10
80°
42°
11
80°
43°
12
79°
43°
13
79°
42°
14
75°
36°
15
68°
34°
16
70°
38°
17
74°
40°
18
79°
42°
19
78°
40°
20
78°
35°
21
75°
40°
22
76°
41°
23
81°
40°
24
78°
40°
25
76°
39°
26
77°
42°
27
79°
40°
28
79°
35°
29
65°
32°
30
63°
38°
1
68°
31°
2
62°
28°
3
60°
33°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Lostine
Lostine's September 2026 forecast shows daily high temperatures ranging from 60° to 81°, with overnight lows between 28° and 45°. The average high for September is 74° 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 Lostine. See also: October | November | December.
