S
M
T
W
T
F
S
30
78°
63°
31
83°
54°
1
77°
51°
2
83°
58°
3
78°
59°
4
85°
53°
5
84°
67°
6
83°
62°
7
78°
63°
8
78°
58°
9
75°
51°
10
83°
46°
11
77°
53°
12
65°
48°
13
67°
41°
14
68°
50°
15
67°
44°
16
64°
49°
17
69°
56°
18
71°
55°
19
71°
51°
20
68°
51°
21
67°
48°
22
71°
51°
23
73°
53°
24
74°
49°
25
74°
50°
26
70°
49°
27
72°
51°
28
58°
47°
29
62°
47°
30
64°
46°
1
68°
46°
2
63°
47°
3
68°
45°
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 58° to 74°, with overnight lows between 44° and 56°. The average high for September is 68° with an average low of 49°. 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.
