S
M
T
W
T
F
S
31
74°
42°
1
66°
47°
2
75°
46°
3
81°
55°
4
84°
54°
5
87°
59°
6
88°
62°
7
81°
63°
8
74°
58°
9
80°
58°
10
82°
60°
11
92°
70°
12
91°
70°
13
85°
67°
14
88°
65°
15
73°
57°
16
75°
52°
17
78°
56°
18
86°
66°
19
81°
67°
20
80°
62°
21
81°
57°
22
70°
60°
23
69°
63°
24
80°
60°
25
82°
63°
26
82°
65°
27
73°
62°
28
83°
63°
29
85°
65°
30
88°
66°
1
89°
71°
2
88°
67°
3
90°
66°
4
89°
66°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
June Weather in New Castle
New Castle's June 2026 forecast shows daily high temperatures ranging from 73° to 90°, with overnight lows between 62° and 71°. The average high for June is 85° with an average low of 65°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how June weather will actually feel in New Castle. See also: July | August | September.