S
M
T
W
T
F
S
30
78°
60°
31
78°
66°
1
78°
63°
2
69°
61°
3
83°
67°
4
82°
68°
5
78°
62°
6
73°
59°
7
77°
53°
8
78°
58°
9
81°
61°
10
84°
69°
11
77°
59°
12
75°
55°
13
77°
64°
14
73°
53°
15
69°
51°
16
78°
56°
17
81°
66°
18
79°
63°
19
68°
59°
20
67°
61°
21
70°
58°
22
68°
51°
23
66°
48°
24
66°
50°
25
70°
54°
26
65°
55°
27
68°
52°
28
72°
54°
29
73°
54°
30
71°
55°
1
74°
55°
2
72°
50°
3
67°
54°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Greenville
Greenville's September 2026 forecast shows daily high temperatures ranging from 65° to 74°, with overnight lows between 48° and 55°. The average high for September is 69° 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 Greenville. See also: October | November | December.