S
M
T
W
T
F
S
30
88°
60°
31
84°
60°
1
88°
56°
2
80°
57°
3
81°
64°
4
88°
65°
5
89°
64°
6
90°
60°
7
87°
61°
8
79°
59°
9
85°
55°
10
79°
54°
11
78°
57°
12
80°
58°
13
79°
60°
14
80°
62°
15
85°
61°
16
84°
50°
17
78°
49°
18
74°
48°
19
72°
50°
20
74°
51°
21
75°
57°
22
80°
60°
23
80°
59°
24
81°
48°
25
80°
47°
26
72°
48°
27
70°
46°
28
69°
45°
29
70°
46°
30
70°
56°
1
68°
49°
2
70°
52°
3
Hist. Avg.
74°
49°
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 68° to 90°, with overnight lows between 45° and 65°. The average high for September is 79° with an average low of 55°. 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.
