S
M
T
W
T
F
S
30
100°
60°
31
100°
71°
1
101°
72°
2
102°
81°
3
101°
74°
4
102°
75°
5
106°
75°
6
105°
73°
7
97°
70°
8
103°
66°
9
100°
79°
10
97°
73°
11
89°
71°
12
96°
70°
13
97°
72°
14
98°
72°
15
98°
76°
16
100°
79°
17
101°
76°
18
100°
72°
19
97°
72°
20
98°
69°
21
89°
68°
22
85°
61°
23
81°
56°
24
81°
57°
25
83°
60°
26
83°
58°
27
82°
59°
28
82°
60°
29
84°
60°
30
84°
61°
1
78°
57°
2
86°
54°
3
81°
60°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Jamestown
Jamestown's September 2026 forecast shows daily high temperatures ranging from 78° to 89°, with overnight lows between 54° and 68°. The average high for September is 83° 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 Jamestown. See also: October | November | December.
