S
M
T
W
T
F
S
30
84°
68°
31
84°
68°
1
85°
65°
2
78°
60°
3
77°
60°
4
77°
61°
5
78°
59°
6
80°
66°
7
84°
66°
8
83°
65°
9
82°
66°
10
84°
66°
11
84°
65°
12
85°
66°
13
84°
67°
14
84°
57°
15
76°
57°
16
75°
56°
17
74°
57°
18
74°
55°
19
73°
54°
20
73°
54°
21
79°
55°
22
79°
60°
23
80°
52°
24
79°
52°
25
72°
51°
26
73°
53°
27
74°
58°
28
77°
58°
29
77°
49°
30
71°
49°
1
69°
57°
2
70°
56°
3
73°
55°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Delaware City
Delaware City's September 2026 forecast shows daily high temperatures ranging from 69° to 85°, with overnight lows between 49° and 68°. The average high for September is 78° 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 Delaware City. See also: October | November | December.
