S
M
T
W
T
F
S
30
75°
59°
31
72°
55°
1
70°
52°
2
68°
57°
3
72°
63°
4
66°
59°
5
68°
55°
6
73°
56°
7
65°
50°
8
61°
47°
9
61°
45°
10
62°
51°
11
66°
50°
12
67°
54°
13
66°
55°
14
67°
56°
15
66°
53°
16
63°
55°
17
62°
54°
18
64°
55°
19
60°
55°
20
64°
57°
21
65°
57°
22
65°
56°
23
64°
56°
24
65°
54°
25
63°
53°
26
61°
49°
27
60°
52°
28
62°
54°
29
62°
54°
30
61°
52°
1
61°
51°
2
62°
53°
3
62°
54°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Grimsby
Grimsby's September 2026 forecast shows daily high temperatures ranging from 60° to 73°, with overnight lows between 45° and 57°. The average high for September is 64° with an average low of 53°. 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 Grimsby. See also: October | November | December.
