S
M
T
W
T
F
S
30
79°
55°
31
68°
57°
1
72°
60°
2
72°
57°
3
76°
56°
4
75°
58°
5
76°
51°
6
77°
57°
7
87°
51°
8
95°
54°
9
94°
63°
10
97°
70°
11
82°
59°
12
74°
58°
13
75°
54°
14
84°
51°
15
80°
52°
16
67°
57°
17
73°
60°
18
80°
54°
19
76°
58°
20
67°
56°
21
71°
57°
22
73°
58°
23
80°
49°
24
91°
56°
25
78°
59°
26
75°
50°
27
72°
52°
28
82°
50°
29
92°
51°
30
96°
56°
1
94°
58°
2
93°
54°
3
94°
56°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Livermore-Pleasanton
Livermore-Pleasanton's September 2026 forecast shows daily high temperatures ranging from 72° to 96°, with overnight lows between 50° and 58°. The average high for September is 89° with an average low of 54°. 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 Livermore-Pleasanton. See also: October | November | December.
