S
M
T
W
T
F
S
30
84°
66°
31
84°
62°
1
81°
60°
2
81°
59°
3
80°
58°
4
80°
57°
5
81°
59°
6
81°
62°
7
82°
58°
8
81°
58°
9
80°
57°
10
81°
62°
11
85°
63°
12
84°
63°
13
85°
62°
14
84°
63°
15
85°
62°
16
84°
62°
17
85°
61°
18
84°
62°
19
83°
61°
20
80°
59°
21
82°
53°
22
76°
51°
23
75°
58°
24
75°
59°
25
Hist. Avg.
78°
56°
26
Hist. Avg.
77°
56°
27
Hist. Avg.
77°
56°
28
Hist. Avg.
76°
55°
29
Hist. Avg.
76°
55°
30
Hist. Avg.
76°
54°
1
Hist. Avg.
75°
54°
2
Hist. Avg.
75°
54°
3
Hist. Avg.
75°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Mount Washington
Mount Washington's September 2026 forecast shows daily high temperatures ranging from 75° to 85°, with overnight lows between 51° and 66°. The average high for September is 82° with an average low of 60°. 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 Mount Washington. See also: October | November | December.
