S
M
T
W
T
F
S
30
93°
70°
31
92°
68°
1
91°
70°
2
93°
70°
3
93°
69°
4
92°
70°
5
92°
69°
6
91°
65°
7
89°
63°
8
85°
62°
9
85°
67°
10
91°
67°
11
90°
66°
12
90°
66°
13
84°
65°
14
88°
67°
15
91°
66°
16
89°
60°
17
83°
59°
18
82°
59°
19
81°
60°
20
82°
58°
21
81°
57°
22
80°
57°
23
80°
61°
24
81°
62°
25
82°
62°
26
87°
61°
27
87°
61°
28
86°
62°
29
86°
61°
30
81°
58°
1
80°
59°
2
84°
53°
3
78°
52°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Houston
Houston's September 2026 forecast shows daily high temperatures ranging from 78° to 93°, with overnight lows between 52° and 70°. The average high for September is 86° 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 Houston. See also: October | November | December.