S
M
T
W
T
F
S
30
92°
65°
31
90°
66°
1
92°
66°
2
92°
67°
3
91°
65°
4
92°
61°
5
88°
62°
6
86°
61°
7
85°
59°
8
84°
60°
9
84°
60°
10
85°
63°
11
86°
64°
12
88°
64°
13
89°
63°
14
89°
62°
15
87°
61°
16
86°
64°
17
87°
65°
18
88°
65°
19
89°
64°
20
90°
64°
21
90°
63°
22
87°
64°
23
84°
61°
24
82°
58°
25
83°
57°
26
81°
59°
27
80°
62°
28
84°
61°
29
85°
59°
30
87°
62°
1
87°
61°
2
Hist. Avg.
84°
59°
3
Hist. Avg.
83°
59°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in El Cajon
El Cajon's September 2026 forecast shows daily high temperatures ranging from 80° to 92°, with overnight lows between 57° and 67°. The average high for September is 87° with an average low of 62°. 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 El Cajon. See also: October | November | December.
