S
M
T
W
T
F
S
30
88°
66°
31
87°
60°
1
83°
58°
2
80°
60°
3
81°
60°
4
82°
60°
5
83°
59°
6
79°
59°
7
79°
58°
8
80°
62°
9
80°
58°
10
78°
57°
11
79°
58°
12
80°
57°
13
79°
58°
14
78°
57°
15
77°
58°
16
79°
55°
17
78°
56°
18
76°
55°
19
77°
60°
20
81°
60°
21
Hist. Avg.
76°
57°
22
Hist. Avg.
76°
57°
23
Hist. Avg.
75°
56°
24
Hist. Avg.
75°
56°
25
Hist. Avg.
75°
56°
26
Hist. Avg.
75°
55°
27
Hist. Avg.
74°
55°
28
Hist. Avg.
74°
55°
29
Hist. Avg.
74°
54°
30
Hist. Avg.
73°
54°
1
Hist. Avg.
73°
54°
2
Hist. Avg.
73°
53°
3
Hist. Avg.
72°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Upper Marlboro
Upper Marlboro's September 2026 forecast shows daily high temperatures ranging from 76° to 88°, with overnight lows between 55° and 66°. The average high for September is 80° 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 Upper Marlboro. See also: October | November | December.
