S
M
T
W
T
F
S
30
98°
78°
31
97°
79°
1
97°
78°
2
100°
78°
3
100°
81°
4
91°
80°
5
97°
77°
6
98°
77°
7
98°
78°
8
100°
78°
9
98°
78°
10
98°
78°
11
100°
79°
12
100°
79°
13
98°
77°
14
98°
78°
15
101°
77°
16
97°
77°
17
92°
74°
18
95°
73°
19
97°
72°
20
96°
71°
21
93°
70°
22
94°
69°
23
93°
71°
24
94°
73°
25
95°
71°
26
89°
66°
27
86°
70°
28
85°
70°
29
87°
69°
30
88°
70°
1
89°
70°
2
88°
69°
3
85°
69°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Alamo Heights
Alamo Heights's September 2026 forecast shows daily high temperatures ranging from 85° to 101°, with overnight lows between 66° and 78°. The average high for September is 92° with an average low of 72°. 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 Alamo Heights. See also: October | November | December.
