S
M
T
W
T
F
S
28
81°
65°
29
85°
64°
30
87°
66°
1
93°
70°
2
98°
79°
3
97°
76°
4
92°
71°
5
81°
65°
6
68°
63°
7
71°
63°
8
80°
64°
9
85°
70°
10
86°
67°
11
80°
63°
12
81°
62°
13
79°
61°
14
82°
61°
15
81°
61°
16
81°
62°
17
83°
63°
18
82°
61°
19
84°
63°
20
80°
58°
21
78°
58°
22
78°
59°
23
81°
59°
24
82°
60°
25
82°
61°
26
84°
62°
27
83°
65°
28
85°
65°
29
85°
64°
30
84°
65°
31
83°
65°
1
84°
64°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
July Weather in New Castle
New Castle's July 2026 forecast shows daily high temperatures ranging from 68° to 86°, with overnight lows between 58° and 70°. The average high for July is 81° with an average low of 63°. 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 New Castle. See also: August | September | October.