S
M
T
W
T
F
S
30
89°
57°
31
80°
58°
1
79°
52°
2
83°
54°
3
85°
55°
4
81°
61°
5
85°
53°
6
87°
56°
7
90°
53°
8
97°
56°
9
102°
67°
10
106°
71°
11
95°
61°
12
93°
62°
13
81°
55°
14
88°
53°
15
90°
54°
16
82°
56°
17
77°
52°
18
85°
52°
19
88°
56°
20
84°
56°
21
84°
54°
22
85°
53°
23
91°
55°
24
97°
61°
25
89°
53°
26
88°
54°
27
81°
50°
28
87°
54°
29
91°
55°
30
97°
56°
1
93°
55°
2
90°
57°
3
93°
59°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Manteca
Manteca's September 2026 forecast shows daily high temperatures ranging from 81° to 97°, with overnight lows between 50° and 61°. The average high for September is 91° 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 Manteca. See also: October | November | December.