S
M
T
W
T
F
S
30
87°
56°
31
86°
55°
1
86°
56°
2
85°
57°
3
86°
57°
4
86°
55°
5
85°
52°
6
82°
51°
7
79°
54°
8
81°
55°
9
84°
55°
10
84°
57°
11
85°
55°
12
82°
54°
13
84°
53°
14
84°
53°
15
81°
51°
16
78°
49°
17
80°
51°
18
84°
54°
19
84°
55°
20
84°
53°
21
83°
55°
22
78°
53°
23
77°
51°
24
78°
53°
25
78°
50°
26
79°
49°
27
77°
48°
28
75°
47°
29
76°
48°
30
76°
49°
1
77°
56°
2
81°
55°
3
83°
54°
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 75° to 87°, with overnight lows between 47° and 57°. The average high for September is 82° 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.
