S
M
T
W
T
F
S
30
68°
56°
31
79°
53°
1
73°
52°
2
76°
58°
3
70°
53°
4
70°
48°
5
74°
54°
6
76°
48°
7
68°
53°
8
74°
48°
9
76°
55°
10
71°
52°
11
66°
50°
12
74°
49°
13
72°
48°
14
74°
47°
15
75°
49°
16
74°
51°
17
76°
52°
18
77°
50°
19
72°
52°
20
71°
50°
21
69°
46°
22
64°
47°
23
63°
46°
24
65°
50°
25
68°
50°
26
63°
48°
27
62°
45°
28
61°
43°
29
60°
41°
30
60°
42°
1
66°
47°
2
69°
48°
3
68°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Lynden
Lynden's September 2026 forecast shows daily high temperatures ranging from 60° to 77°, with overnight lows between 41° and 55°. The average high for September is 69° with an average low of 48°. 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 Lynden. See also: October | November | December.
