S
M
T
W
T
F
S
30
71°
51°
31
N/A
1
71°
59°
2
69°
61°
3
71°
60°
4
76°
57°
5
71°
49°
6
77°
51°
7
78°
53°
8
72°
51°
9
75°
57°
10
77°
54°
11
75°
47°
12
71°
48°
13
74°
53°
14
68°
50°
15
67°
47°
16
69°
53°
17
73°
50°
18
64°
46°
19
65°
43°
20
69°
49°
21
72°
53°
22
72°
53°
23
71°
51°
24
71°
50°
25
70°
48°
26
70°
50°
27
71°
51°
28
70°
48°
29
67°
43°
30
58°
40°
1
58°
39°
2
61°
48°
3
67°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in St. Johnsbury
St. Johnsbury's September 2026 forecast shows daily high temperatures ranging from 58° to 78°, with overnight lows between 39° and 61°. The average high for September is 70° with an average low of 50°. 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 St. Johnsbury. See also: October | November | December.
