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
87°
71°
8
97°
73°
9
104°
73°
10
104°
70°
11
99°
65°
12
94°
65°
13
93°
65°
14
94°
64°
15
92°
65°
16
92°
66°
17
94°
66°
18
92°
64°
19
91°
63°
20
89°
60°
21
86°
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 104°, with overnight lows between 57° and 73°. The average high for September is 90° 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.
