S
M
T
W
T
F
S
30
77°
43°
31
73°
39°
1
73°
43°
2
73°
57°
3
70°
59°
4
77°
60°
5
71°
51°
6
73°
46°
7
79°
42°
8
71°
45°
9
67°
45°
10
70°
46°
11
67°
40°
12
73°
38°
13
71°
50°
14
63°
39°
15
64°
35°
16
74°
46°
17
69°
45°
18
65°
35°
19
62°
34°
20
59°
39°
21
60°
36°
22
N/A
23
67°
35°
24
73°
34°
25
74°
41°
26
73°
47°
27
69°
51°
28
62°
47°
29
62°
46°
30
66°
48°
1
69°
48°
2
68°
48°
3
65°
44°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Portneuf
Portneuf's September 2026 forecast shows daily high temperatures ranging from 62° to 74°, with overnight lows between 41° and 51°. The average high for September is 68° with an average low of 47°. 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 Portneuf. See also: October | November | December.
