S
M
T
W
T
F
S
30
96°
70°
31
91°
64°
1
91°
58°
2
88°
53°
3
86°
56°
4
89°
57°
5
94°
56°
6
77°
66°
7
86°
70°
8
96°
73°
9
105°
74°
10
104°
70°
11
99°
65°
12
94°
61°
13
90°
63°
14
92°
64°
15
92°
65°
16
93°
66°
17
92°
63°
18
95°
64°
19
94°
65°
20
92°
64°
21
90°
61°
22
85°
59°
23
85°
58°
24
84°
60°
25
85°
59°
26
86°
59°
27
83°
57°
28
87°
60°
29
88°
61°
30
86°
60°
1
84°
58°
2
89°
61°
3
88°
61°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in San Jacinto
San Jacinto's September 2026 forecast shows daily high temperatures ranging from 83° to 105°, with overnight lows between 57° and 74°. The average high for September is 91° with an average low of 63°. 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 San Jacinto. See also: October | November | December.
