S
M
T
W
T
F
S
30
85°
60°
31
85°
70°
1
93°
71°
2
79°
72°
3
90°
73°
4
89°
68°
5
82°
62°
6
79°
61°
7
80°
61°
8
82°
63°
9
86°
69°
10
88°
64°
11
84°
61°
12
81°
60°
13
83°
63°
14
81°
62°
15
85°
60°
16
83°
58°
17
75°
56°
18
74°
54°
19
79°
57°
20
81°
60°
21
80°
60°
22
78°
59°
23
74°
59°
24
78°
57°
25
76°
57°
26
79°
59°
27
79°
58°
28
76°
53°
29
70°
51°
30
72°
54°
1
70°
51°
2
70°
53°
3
68°
49°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Mount Pleasant
Mount Pleasant's September 2026 forecast shows daily high temperatures ranging from 68° to 90°, with overnight lows between 49° and 73°. The average high for September is 79° with an average low of 59°. 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 Mount Pleasant. See also: October | November | December.
