S
M
T
W
T
F
S
30
100°
78°
31
N/A
1
103°
79°
2
104°
81°
3
101°
81°
4
101°
79°
5
100°
78°
6
99°
77°
7
99°
78°
8
98°
77°
9
98°
78°
10
97°
77°
11
97°
79°
12
95°
77°
13
96°
78°
14
92°
73°
15
89°
75°
16
90°
73°
17
93°
73°
18
92°
75°
19
90°
74°
20
91°
74°
21
91°
75°
22
90°
74°
23
88°
74°
24
87°
73°
25
86°
73°
26
87°
74°
27
86°
73°
28
86°
73°
29
87°
70°
30
86°
70°
1
86°
72°
2
87°
72°
3
86°
71°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Weslaco
Weslaco's September 2026 forecast shows daily high temperatures ranging from 86° to 104°, with overnight lows between 70° and 81°. The average high for September is 93° with an average low of 75°. 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 Weslaco. See also: October | November | December.
