S
M
T
W
T
F
S
30
101°
78°
31
101°
80°
1
100°
80°
2
100°
79°
3
93°
77°
4
100°
78°
5
100°
78°
6
100°
78°
7
101°
79°
8
102°
82°
9
101°
82°
10
100°
78°
11
98°
78°
12
101°
75°
13
100°
80°
14
100°
79°
15
102°
80°
16
101°
81°
17
99°
78°
18
97°
76°
19
98°
78°
20
98°
74°
21
96°
71°
22
92°
72°
23
94°
71°
24
90°
68°
25
88°
67°
26
89°
68°
27
88°
69°
28
85°
63°
29
86°
68°
30
87°
68°
1
87°
67°
2
86°
68°
3
86°
67°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Arlington
Arlington's September 2026 forecast shows daily high temperatures ranging from 85° to 102°, with overnight lows between 63° and 81°. The average high for September is 92° with an average low of 71°. 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 Arlington. See also: October | November | December.