S
M
T
W
T
F
S
30
91°
70°
31
93°
70°
1
96°
70°
2
98°
72°
3
97°
73°
4
97°
72°
5
100°
72°
6
97°
71°
7
82°
73°
8
90°
69°
9
92°
66°
10
92°
67°
11
93°
70°
12
86°
71°
13
91°
72°
14
93°
68°
15
88°
73°
16
89°
71°
17
91°
65°
18
96°
68°
19
93°
72°
20
90°
71°
21
92°
69°
22
86°
70°
23
80°
66°
24
72°
62°
25
77°
60°
26
82°
54°
27
82°
48°
28
81°
50°
29
84°
51°
30
86°
58°
1
86°
61°
2
87°
66°
3
85°
68°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Duluth
Duluth's September 2026 forecast shows daily high temperatures ranging from ° to °, with overnight lows between ° and °. The average high for September is ° with an average low of °. 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 Duluth. See also: October | November | December.
