S
M
T
W
T
F
S
30
82°
73°
31
80°
69°
1
79°
68°
2
79°
65°
3
78°
66°
4
78°
65°
5
85°
65°
6
79°
69°
7
92°
75°
8
99°
75°
9
102°
78°
10
89°
77°
11
83°
74°
12
80°
72°
13
79°
71°
14
79°
69°
15
78°
69°
16
78°
68°
17
79°
70°
18
78°
66°
19
79°
65°
20
79°
69°
21
77°
69°
22
79°
70°
23
80°
66°
24
77°
69°
25
81°
69°
26
88°
68°
27
86°
71°
28
79°
68°
29
81°
64°
30
77°
67°
1
82°
67°
2
100°
67°
3
102°
72°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Irvine
Irvine's September 2026 forecast shows daily high temperatures ranging from ° to °, with overnight lows between ° and °. The average high for September is ° with an average low of °. 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 Irvine. See also: October | November | December.
