S
M
T
W
T
F
S
30
102°
79°
31
101°
74°
1
100°
74°
2
101°
80°
3
99°
77°
4
100°
75°
5
101°
77°
6
102°
72°
7
103°
77°
8
105°
80°
9
106°
73°
10
91°
72°
11
99°
72°
12
100°
73°
13
101°
71°
14
94°
65°
15
84°
57°
16
86°
61°
17
87°
58°
18
83°
56°
19
78°
56°
20
81°
59°
21
83°
58°
22
88°
64°
23
89°
64°
24
85°
63°
25
76°
63°
26
80°
62°
27
81°
62°
28
83°
61°
29
81°
62°
30
83°
52°
1
71°
48°
2
72°
48°
3
70°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Blackwell
Blackwell's September 2026 forecast shows daily high temperatures ranging from 70° to 106°, with overnight lows between 47° and 80°. The average high for September is 86° with an average low of 62°. 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 Blackwell. See also: October | November | December.