S
M
T
W
T
F
S
26
69°
48°
27
68°
47°
28
69°
46°
29
73°
48°
30
77°
49°
1
78°
49°
2
71°
44°
3
68°
45°
4
70°
48°
5
65°
44°
6
66°
47°
7
67°
48°
8
67°
46°
9
66°
43°
10
67°
43°
11
67°
44°
12
68°
43°
13
68°
48°
14
67°
44°
15
67°
45°
16
66°
45°
17
68°
44°
18
68°
46°
19
69°
51°
20
70°
51°
21
70°
50°
22
69°
47°
23
69°
45°
24
72°
47°
25
74°
49°
26
76°
51°
27
74°
51°
28
73°
50°
29
71°
52°
30
76°
51°
31
78°
53°
1
75°
53°
2
77°
53°
3
81°
51°
4
79°
52°
5
76°
50°
6
77°
51°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Rockville
Rockville's May 2026 forecast shows daily high temperatures ranging from 65° to 81°, with overnight lows between 43° and 53°. The average high for May is 71° with an average low of 48°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how May weather will actually feel in Rockville. See also: June | July | August.