S
M
T
W
T
F
S
30
105°
81°
31
105°
81°
1
105°
80°
2
106°
82°
3
106°
83°
4
106°
83°
5
105°
75°
6
104°
78°
7
105°
80°
8
106°
82°
9
104°
81°
10
107°
79°
11
106°
82°
12
104°
82°
13
101°
81°
14
100°
81°
15
103°
78°
16
102°
77°
17
91°
75°
18
94°
74°
19
97°
75°
20
100°
76°
21
96°
75°
22
95°
75°
23
96°
74°
24
96°
75°
25
95°
73°
26
92°
71°
27
94°
74°
28
91°
74°
29
93°
75°
30
94°
74°
1
93°
74°
2
91°
73°
3
93°
74°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Mission
Mission's September 2026 forecast shows daily high temperatures ranging from 91° to 103°, with overnight lows between 71° and 81°. The average high for September is 96° 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 Mission. See also: October | November | December.
