S
M
T
W
T
F
S
30
81°
61°
31
80°
61°
1
80°
62°
2
81°
63°
3
79°
65°
4
79°
62°
5
81°
62°
6
80°
61°
7
79°
60°
8
78°
59°
9
78°
60°
10
79°
63°
11
78°
58°
12
77°
59°
13
78°
58°
14
79°
62°
15
79°
64°
16
81°
61°
17
76°
57°
18
75°
56°
19
75°
57°
20
78°
62°
21
76°
56°
22
74°
58°
23
79°
61°
24
78°
62°
25
79°
60°
26
78°
53°
27
77°
54°
28
70°
53°
29
69°
52°
30
71°
52°
1
70°
52°
2
Hist. Avg.
73°
55°
3
Hist. Avg.
72°
54°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Merion
Merion's September 2026 forecast shows daily high temperatures ranging from 69° to 81°, with overnight lows between 52° and 65°. The average high for September is 77° with an average low of 59°. 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 Merion. See also: October | November | December.
