S
M
T
W
T
F
S
30
85°
62°
31
81°
54°
1
65°
49°
2
66°
50°
3
63°
55°
4
64°
52°
5
70°
54°
6
72°
55°
7
79°
59°
8
86°
64°
9
91°
73°
10
91°
75°
11
86°
72°
12
82°
59°
13
75°
58°
14
84°
60°
15
84°
60°
16
81°
57°
17
79°
60°
18
86°
54°
19
87°
53°
20
83°
55°
21
84°
54°
22
81°
55°
23
85°
54°
24
86°
56°
25
87°
58°
26
81°
48°
27
77°
48°
28
76°
44°
29
79°
45°
30
79°
46°
1
83°
50°
2
80°
46°
3
80°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Challenge-Brownsville
Challenge-Brownsville's September 2026 forecast shows daily high temperatures ranging from 75° to 87°, with overnight lows between 44° and 60°. The average high for September is 82° 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 Challenge-Brownsville. See also: October | November | December.
