S
M
T
W
T
F
S
27
76°
59°
28
76°
63°
29
75°
66°
30
80°
65°
1
87°
67°
2
89°
70°
3
77°
65°
4
71°
67°
5
71°
62°
6
66°
52°
7
71°
49°
8
83°
62°
9
77°
60°
10
75°
66°
11
76°
67°
12
77°
60°
13
79°
60°
14
71°
56°
15
69°
58°
16
74°
60°
17
72°
55°
18
62°
53°
19
64°
52°
20
67°
52°
21
68°
51°
22
68°
56°
23
64°
52°
24
62°
50°
25
63°
53°
26
66°
53°
27
69°
50°
28
63°
46°
29
59°
44°
30
60°
48°
31
63°
52°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
October Weather in Portsmouth
Portsmouth's October 2026 forecast shows daily high temperatures ranging from 59° to 83°, with overnight lows between 44° and 67°. The average high for October is 69° with an average low of 55°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how October weather will actually feel in Portsmouth. See also: November | December | January.
