S
M
T
W
T
F
S
30
91°
70°
31
87°
66°
1
85°
64°
2
82°
62°
3
82°
61°
4
83°
63°
5
91°
59°
6
89°
71°
7
100°
75°
8
95°
71°
9
98°
72°
10
90°
69°
11
86°
69°
12
82°
64°
13
81°
63°
14
80°
65°
15
79°
67°
16
81°
66°
17
82°
67°
18
83°
66°
19
82°
67°
20
81°
66°
21
80°
62°
22
76°
60°
23
75°
60°
24
75°
59°
25
76°
61°
26
76°
61°
27
75°
60°
28
77°
62°
29
79°
62°
30
82°
63°
1
82°
63°
2
81°
62°
3
82°
63°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Vista
Vista's September 2026 forecast shows daily high temperatures ranging from 75° to 98°, with overnight lows between 59° and 72°. The average high for September is 81° with an average low of 64°. 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 Vista. See also: October | November | December.