S
M
T
W
T
F
S
30
102°
70°
31
101°
76°
1
99°
73°
2
101°
75°
3
101°
71°
4
100°
72°
5
99°
73°
6
99°
72°
7
98°
71°
8
100°
70°
9
98°
71°
10
100°
71°
11
92°
68°
12
95°
69°
13
93°
68°
14
84°
66°
15
90°
66°
16
90°
65°
17
89°
66°
18
91°
66°
19
90°
65°
20
90°
65°
21
89°
64°
22
88°
64°
23
88°
63°
24
83°
63°
25
82°
62°
26
81°
61°
27
79°
62°
28
79°
60°
29
81°
61°
30
82°
61°
1
82°
60°
2
83°
60°
3
82°
59°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Carlsbad
Carlsbad's September 2026 forecast shows daily high temperatures ranging from 79° to 101°, with overnight lows between 59° and 75°. The average high for September is 90° with an average low of 66°. 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 Carlsbad. See also: October | November | December.
