Boulder Mountains (Montana)
Mountain range in Montana, United States
From Wikipedia, the free encyclopedia
The Boulder Mountains are a mountain range running roughly north to south located west of Boulder between Helena and Butte in the U.S. state of Montana.[1] Parts of the range are in four different counties: Deer Lodge, Jefferson, Lewis and Clark, and Silver Bow.[1]
| Boulder Mountains | |
|---|---|
 | |
| Highest point | |
| Peak | Haystack Mountain |
| Elevation | 8,819 ft (2,688 m) |
| Coordinates | 46°08′29″N 112°19′35″W |
| Geography | |
| Country | United States |
| State | Montana |
| Parent range | Rocky Mountains |
Haystack Mountain, which reaches 8,819 feet (2,688 m), is the tallest peak in the range.[2][3] The three other highest peaks are Jack Mountain at 8,752 feet (2,668 m), Bull Mountain at 8,609 feet (2,624 m), and Thunderbolt Mountain at 8,597 feet (2,620 m).[2] All four peaks are in Jefferson County.[2]
Climate
Rocker Peak, 8,455 ft (2,577 m),[4] is near Jack Mountain (Montana), the second highest peak in the Boulder Mountains.[5] There is a SNOTEL weather station near the summit of Rocker Peak at an elevation of 8,000 ft (2,438 m). Rocker Peak has a subalpine climate (Köppen Dfc), bordering on an alpine climate (Köppen ETH).
| Climate data for Rocker Peak, Montana (elevation 8,000 feet or 2,438 meters): 1991–2020 normals; 1983–2020 extremes | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Record high °F (°C) | 55 (13) |
53 (12) |
58 (14) |
66 (19) |
73 (23) |
81 (27) |
85 (29) |
85 (29) |
81 (27) |
72 (22) |
59 (15) |
48 (9) |
85 (29) |
| Mean maximum °F (°C) | 43.2 (6.2) |
43.4 (6.3) |
49.6 (9.8) |
56.5 (13.6) |
63.8 (17.7) |
71.4 (21.9) |
77.1 (25.1) |
76.2 (24.6) |
72.1 (22.3) |
62.1 (16.7) |
49.0 (9.4) |
40.7 (4.8) |
78.2 (25.7) |
| Mean daily maximum °F (°C) | 26.8 (−2.9) |
27.6 (−2.4) |
34.2 (1.2) |
39.6 (4.2) |
48.0 (8.9) |
55.8 (13.2) |
66.4 (19.1) |
65.4 (18.6) |
55.8 (13.2) |
42.4 (5.8) |
31.6 (−0.2) |
25.1 (−3.8) |
43.2 (6.2) |
| Daily mean °F (°C) | 20.2 (−6.6) |
19.8 (−6.8) |
25.5 (−3.6) |
30.5 (−0.8) |
38.8 (3.8) |
45.9 (7.7) |
54.9 (12.7) |
54.1 (12.3) |
46.1 (7.8) |
34.5 (1.4) |
24.9 (−3.9) |
18.9 (−7.3) |
34.5 (1.4) |
| Mean daily minimum °F (°C) | 13.6 (−10.2) |
12.2 (−11.0) |
16.8 (−8.4) |
21.4 (−5.9) |
29.6 (−1.3) |
36.0 (2.2) |
43.5 (6.4) |
42.9 (6.1) |
36.3 (2.4) |
26.7 (−2.9) |
18.2 (−7.7) |
12.6 (−10.8) |
25.8 (−3.4) |
| Mean minimum °F (°C) | −8.1 (−22.3) |
−8.8 (−22.7) |
−2.0 (−18.9) |
7.0 (−13.9) |
16.6 (−8.6) |
26.6 (−3.0) |
34.0 (1.1) |
32.2 (0.1) |
22.3 (−5.4) |
8.4 (−13.1) |
−1.2 (−18.4) |
−7.8 (−22.1) |
−19.7 (−28.7) |
| Record low °F (°C) | −30 (−34) |
−42 (−41) |
−24 (−31) |
−8 (−22) |
7 (−14) |
16 (−9) |
16 (−9) |
16 (−9) |
4 (−16) |
−11 (−24) |
−27 (−33) |
−39 (−39) |
−42 (−41) |
| Average precipitation inches (mm) | 2.07 (53) |
2.16 (55) |
2.58 (66) |
3.50 (89) |
3.58 (91) |
4.08 (104) |
1.72 (44) |
1.52 (39) |
1.80 (46) |
2.16 (55) |
2.24 (57) |
2.11 (54) |
29.52 (753) |
| Source 1: XMACIS2[6] | |||||||||||||
| Source 2: NOAA (Precipitation)[7] | |||||||||||||