S
M
T
W
T
F
S
30
84°
43°
31
75°
43°
1
72°
52°
2
74°
54°
3
82°
46°
4
77°
43°
5
71°
46°
6
74°
52°
7
79°
42°
8
81°
38°
9
69°
39°
10
66°
40°
11
64°
38°
12
65°
38°
13
66°
43°
14
67°
47°
15
69°
50°
16
74°
42°
17
76°
40°
18
64°
44°
19
63°
45°
20
70°
40°
21
67°
43°
22
68°
38°
23
62°
37°
24
61°
39°
25
67°
42°
26
60°
32°
27
60°
33°
28
Hist. Avg.
61°
37°
29
Hist. Avg.
61°
36°
30
Hist. Avg.
60°
36°
1
Hist. Avg.
60°
36°
2
Hist. Avg.
60°
35°
3
Hist. Avg.
59°
35°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Neptune
Neptune's September 2026 forecast shows daily high temperatures ranging from 60° to 84°, with overnight lows between 32° and 54°. The average high for September is 70° with an average low of 42°. 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 Neptune. See also: October | November | December.
