S
M
T
W
T
F
S
26
100°
67°
27
90°
68°
28
89°
64°
29
83°
64°
30
92°
64°
31
88°
60°
1
92°
59°
2
100°
56°
3
102°
59°
4
71°
54°
5
80°
50°
6
95°
51°
7
91°
54°
8
98°
56°
9
96°
61°
10
95°
64°
11
96°
61°
12
91°
56°
13
81°
63°
14
85°
60°
15
81°
57°
16
86°
60°
17
92°
54°
18
87°
57°
19
89°
60°
20
92°
55°
21
99°
59°
22
90°
56°
23
94°
62°
24
93°
57°
25
83°
57°
26
82°
55°
27
90°
54°
28
96°
66°
29
92°
64°
30
89°
60°
31
82°
58°
1
89°
57°
2
90°
60°
3
86°
60°
4
89°
61°
5
91°
60°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Longmont
Longmont's August 2026 forecast shows daily high temperatures ranging from 82° to 96°, with overnight lows between 57° and 66°. The average high for August is 89° with an average low of 61°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how August weather will actually feel in Longmont. See also: September | October | November.
