S
M
T
W
T
F
S
30
77°
50°
31
72°
49°
1
69°
59°
2
71°
59°
3
71°
55°
4
72°
53°
5
77°
50°
6
77°
51°
7
86°
50°
8
91°
54°
9
99°
66°
10
98°
67°
11
94°
54°
12
79°
53°
13
77°
50°
14
84°
54°
15
76°
55°
16
71°
54°
17
75°
54°
18
82°
55°
19
78°
54°
20
80°
53°
21
81°
55°
22
81°
56°
23
82°
55°
24
83°
55°
25
84°
56°
26
82°
52°
27
76°
52°
28
76°
50°
29
77°
52°
30
78°
51°
1
82°
54°
2
75°
53°
3
77°
51°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Larkspur
Larkspur's September 2026 forecast shows daily high temperatures ranging from 71° to 84°, with overnight lows between 50° and 56°. The average high for September is 79° with an average low of 53°. 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 Larkspur. See also: October | November | December.
