S
M
T
W
T
F
S
30
77°
55°
31
73°
57°
1
75°
62°
2
78°
59°
3
81°
57°
4
78°
54°
5
82°
53°
6
78°
51°
7
85°
55°
8
87°
60°
9
83°
60°
10
82°
58°
11
85°
57°
12
83°
56°
13
82°
57°
14
84°
57°
15
82°
58°
16
83°
55°
17
84°
56°
18
79°
57°
19
85°
56°
20
85°
57°
21
84°
57°
22
85°
56°
23
80°
57°
24
81°
54°
25
84°
57°
26
86°
58°
27
86°
58°
28
85°
57°
29
84°
58°
30
85°
56°
1
84°
57°
2
81°
56°
3
77°
55°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Monte Sereno
Monte Sereno's September 2026 forecast shows daily high temperatures ranging from 77° to 87°, with overnight lows between 51° and 60°. The average high for September is 83° with an average low of 56°. 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 Monte Sereno. See also: October | November | December.
