S
M
T
W
T
F
S
27
49°
16°
28
43°
16°
29
41°
19°
30
43°
15°
31
41°
17°
1
41°
24°
2
45°
25°
3
45°
18°
4
43°
17°
5
43°
15°
6
42°
16°
7
42°
17°
8
43°
18°
9
43°
19°
10
45°
19°
11
45°
15°
12
42°
17°
13
43°
17°
14
45°
19°
15
45°
18°
16
46°
16°
17
42°
18°
18
42°
20°
19
44°
22°
20
48°
28°
21
49°
24°
22
44°
19°
23
45°
20°
24
44°
19°
25
42°
17°
26
43°
18°
27
42°
21°
28
43°
24°
29
46°
27°
30
42°
17°
31
40°
16°
1
Hist. Avg.
47°
21°
2
Hist. Avg.
47°
21°
3
Hist. Avg.
47°
21°
4
Hist. Avg.
47°
21°
5
Hist. Avg.
47°
21°
6
Hist. Avg.
47°
21°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
January Weather in Boulder
Boulder's January 2027 forecast shows daily high temperatures ranging from 40° to 49°, with overnight lows between 15° and 28°. The average high for January is 44° with an average low of 19°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how January weather will actually feel in Boulder. See also: February | March | April.
