S
M
T
W
T
F
S
30
77°
36°
31
86°
36°
1
81°
47°
2
63°
45°
3
61°
41°
4
57°
39°
5
66°
36°
6
61°
45°
7
68°
37°
8
77°
37°
9
86°
39°
10
84°
43°
11
75°
45°
12
73°
34°
13
61°
41°
14
68°
32°
15
70°
36°
16
68°
46°
17
61°
46°
18
73°
39°
19
81°
40°
20
85°
43°
21
84°
45°
22
80°
41°
23
76°
44°
24
75°
44°
25
73°
43°
26
72°
40°
27
73°
42°
28
73°
41°
29
74°
42°
30
70°
42°
1
69°
41°
2
74°
38°
3
66°
37°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Prineville
Prineville's September 2026 forecast shows daily high temperatures ranging from 66° to 85°, with overnight lows between 37° and 45°. The average high for September is 75° with an average low of 42°. 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 Prineville. See also: October | November | December.
