S
M
T
W
T
F
S
30
76°
53°
31
90°
51°
1
81°
63°
2
78°
56°
3
69°
50°
4
70°
51°
5
72°
52°
6
72°
54°
7
75°
57°
8
77°
58°
9
81°
58°
10
83°
59°
11
75°
57°
12
76°
58°
13
78°
58°
14
76°
57°
15
80°
61°
16
83°
56°
17
71°
51°
18
71°
49°
19
70°
48°
20
71°
58°
21
72°
54°
22
76°
58°
23
72°
49°
24
68°
46°
25
67°
46°
26
68°
48°
27
76°
52°
28
78°
54°
29
77°
55°
30
78°
54°
1
77°
55°
2
77°
55°
3
76°
54°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Walla Walla Regional Airport
Walla Walla Regional Airport's September 2026 forecast shows daily high temperatures ranging from 67° to 83°, with overnight lows between 46° and 61°. The average high for September is 75° with an average low of 54°. 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 Walla Walla Regional Airport. See also: October | November | December.
