S
M
T
W
T
F
S
30
83°
56°
31
86°
57°
1
87°
57°
2
87°
55°
3
83°
57°
4
82°
57°
5
85°
56°
6
87°
57°
7
87°
56°
8
86°
57°
9
86°
53°
10
82°
50°
11
81°
50°
12
82°
51°
13
80°
52°
14
80°
51°
15
82°
52°
16
84°
54°
17
83°
57°
18
86°
58°
19
78°
58°
20
78°
57°
21
83°
57°
22
85°
58°
23
82°
57°
24
83°
57°
25
84°
55°
26
83°
56°
27
84°
55°
28
79°
56°
29
78°
56°
30
78°
55°
1
83°
56°
2
84°
55°
3
83°
54°
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 78° to 87°, with overnight lows between 50° and 58°. The average high for September is 83° with an average low of 55°. 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.
