S
M
T
W
T
F
S
28
86°
67°
29
92°
67°
30
93°
71°
1
98°
72°
2
99°
75°
3
97°
74°
4
95°
73°
5
94°
71°
6
92°
72°
7
90°
71°
8
89°
68°
9
86°
70°
10
87°
70°
11
88°
69°
12
90°
71°
13
92°
69°
14
89°
65°
15
81°
61°
16
82°
62°
17
82°
62°
18
83°
63°
19
87°
68°
20
86°
68°
21
83°
67°
22
83°
68°
23
88°
69°
24
88°
68°
25
89°
68°
26
89°
69°
27
88°
69°
28
89°
68°
29
89°
70°
30
90°
69°
31
88°
68°
1
82°
67°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
July Weather in Portsmouth
Portsmouth's July 2026 forecast shows daily high temperatures ranging from 81° to 99°, with overnight lows between 61° and 75°. The average high for July is 89° with an average low of 69°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how July weather will actually feel in Portsmouth. See also: August | September | October.
