S
M
T
W
T
F
S
30
88°
56°
31
80°
54°
1
79°
60°
2
80°
59°
3
81°
55°
4
83°
62°
5
86°
61°
6
87°
54°
7
81°
54°
8
78°
53°
9
77°
53°
10
78°
57°
11
83°
53°
12
77°
53°
13
76°
52°
14
75°
58°
15
81°
59°
16
82°
50°
17
81°
49°
18
73°
48°
19
72°
50°
20
72°
54°
21
71°
53°
22
71°
49°
23
70°
51°
24
71°
50°
25
72°
54°
26
76°
55°
27
77°
47°
28
76°
46°
29
69°
52°
30
70°
53°
1
69°
54°
2
71°
51°
3
73°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Round Top
Round Top's September 2026 forecast shows daily high temperatures ranging from 69° to 88°, with overnight lows between 45° and 62°. The average high for September is 77° with an average low of 53°. 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 Round Top. See also: October | November | December.
