S
M
T
W
T
F
S
30
70°
54°
31
70°
55°
1
69°
54°
2
68°
54°
3
69°
52°
4
67°
49°
5
64°
50°
6
66°
54°
7
65°
50°
8
66°
51°
9
65°
53°
10
67°
48°
11
66°
48°
12
66°
49°
13
65°
49°
14
62°
51°
15
63°
47°
16
61°
46°
17
61°
45°
18
62°
49°
19
62°
48°
20
61°
47°
21
61°
46°
22
60°
47°
23
60°
49°
24
61°
47°
25
60°
47°
26
62°
49°
27
Hist. Avg.
62°
48°
28
Hist. Avg.
62°
48°
29
Hist. Avg.
61°
48°
30
Hist. Avg.
61°
48°
1
Hist. Avg.
61°
47°
2
Hist. Avg.
61°
47°
3
Hist. Avg.
60°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Upper Swell
Upper Swell's September 2026 forecast shows daily high temperatures ranging from 60° to 70°, with overnight lows between 45° and 55°. The average high for September is 64° with an average low of 50°. 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 Upper Swell. See also: October | November | December.