S
M
T
W
T
F
S
30
102°
77°
31
100°
74°
1
94°
59°
2
94°
62°
3
94°
62°
4
91°
61°
5
92°
67°
6
86°
68°
7
90°
69°
8
92°
70°
9
93°
67°
10
94°
66°
11
100°
70°
12
98°
68°
13
97°
69°
14
94°
64°
15
98°
69°
16
97°
68°
17
96°
67°
18
94°
62°
19
89°
62°
20
91°
63°
21
93°
64°
22
94°
65°
23
93°
63°
24
90°
59°
25
83°
56°
26
82°
56°
27
81°
55°
28
82°
55°
29
84°
57°
30
84°
58°
1
83°
56°
2
86°
59°
3
89°
62°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Barstow
Barstow's September 2026 forecast shows daily high temperatures ranging from 81° to 100°, with overnight lows between 55° and 70°. The average high for September is 91° 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 Barstow. See also: October | November | December.
