S
M
T
W
T
F
S
26
58°
44°
27
71°
39°
28
62°
46°
29
62°
52°
30
69°
43°
1
67°
38°
2
61°
49°
3
63°
42°
4
78°
44°
5
85°
55°
6
72°
60°
7
65°
53°
8
73°
41°
9
75°
55°
10
83°
48°
11
63°
47°
12
71°
40°
13
76°
57°
14
63°
53°
15
72°
52°
16
86°
47°
17
88°
58°
18
98°
69°
19
101°
71°
20
97°
60°
21
66°
53°
22
60°
57°
23
73°
63°
24
75°
63°
25
79°
64°
26
80°
63°
27
80°
63°
28
79°
62°
29
82°
63°
30
81°
62°
31
83°
61°
1
84°
65°
2
79°
64°
3
77°
66°
4
80°
65°
5
78°
62°
6
79°
66°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Mount Rainier
Mount Rainier's May 2026 forecast shows daily high temperatures ranging from 60° to 101°, with overnight lows between 53° and 71°. The average high for May 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 May weather will actually feel in Mount Rainier. See also: June | July | August.
