S
M
T
W
T
F
S
30
72°
57°
31
65°
61°
1
82°
57°
2
78°
52°
3
74°
49°
4
69°
58°
5
77°
51°
6
77°
48°
7
69°
56°
8
71°
63°
9
72°
52°
10
69°
43°
11
80°
47°
12
69°
53°
13
64°
40°
14
65°
34°
15
68°
43°
16
64°
39°
17
69°
40°
18
57°
34°
19
60°
49°
20
57°
40°
21
58°
40°
22
59°
43°
23
60°
45°
24
63°
44°
25
66°
48°
26
65°
49°
27
64°
45°
28
63°
46°
29
63°
43°
30
61°
43°
1
62°
47°
2
61°
36°
3
57°
43°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Grand Portage Ut
Grand Portage Ut's September 2026 forecast shows daily high temperatures ranging from 57° to 66°, with overnight lows between 36° and 49°. The average high for September is 61° with an average low of 44°. 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 Grand Portage Ut. See also: October | November | December.
