Boulder River (Sweet Grass County, Montana)

Boulder River
A section of the upper Boulder River
Map
Location
CountryPark and Sweet Grass County, Montana
Physical characteristics
Source 
 • coordinates45°10′25″N 110°13′31″W / 45.17361°N 110.22528°W / 45.17361; -110.22528 (Boulder River)[1]
Mouth 
 • coordinates
45°51′10″N 109°55′25″W / 45.85278°N 109.92361°W / 45.85278; -109.92361 (Boulder River)[1]
 • elevation
4,003 feet (1,220 m)[1]
Basin features
River systemYellowstone River

The Boulder River is a tributary of the Yellowstone River, approximately 60 mi (96 km) long, in south central Montana in the United States. It is one of two rivers named the Boulder River in Montana.

It rises in the Gallatin National Forest in the Absaroka Range in southern Park County. It flows north through mountainous canyons, a cataract under a natural bridge, and northwest in a widening valley past McLeod. It joins the Yellowstone at Big Timber. The landscape of the Boulder River and river valley has merited the filming of two movies: A River Runs Through It and The Horse Whisperer.[2]

Discharges

River Location Discharge
East Boulder River near McLeod 80 cu ft/s (2.3 m3/s)[3]
West Boulder River McLeod 189 cu ft/s (5.4 m3/s)[4]
Boulder River Big Timber 563 cu ft/s (15.9 m3/s)[5]

Tourism

The river is a popular destination for fly fishing. Other attractions in the valley include several church camps, a guest ranch, and several USFS campgrounds. The Forest Service also maintains several guard stations, trailheads, and picnic areas in the valley.[6]

Variant names

The Boulder River has also been known as: Rivers a Cross, Rivers across, and Rivers-across.[1] And, to distinguish it from the other Boulder River in Montana, it is sometimes called the "East Boulder River" (as it is east of the other) or the "Boulder Fork of the Yellowstone," parallel with the Clark's Fork of the Yellowstone as differentiated from the Clark's Fork River of Western Montana.

Climate

The Placer Basin SNOTEL weather station is situated near the source of the East Boulder River, at an elevation of 8830 feet (2691 m).

Climate data for Placer Basin, Montana, 1991–2020 normals: 8830ft (2691m)
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Record high °F (°C) 54
(12) 		55
(13) 		57
(14) 		66
(19) 		71
(22) 		78
(26) 		82
(28) 		83
(28) 		77
(25) 		71
(22) 		59
(15) 		50
(10) 		83
(28)
Mean maximum °F (°C) 43.8
(6.6) 		44.6
(7.0) 		51.8
(11.0) 		58.7
(14.8) 		65.5
(18.6) 		72.1
(22.3) 		76.8
(24.9) 		75.9
(24.4) 		72.1
(22.3) 		61.9
(16.6) 		50.1
(10.1) 		40.5
(4.7) 		77.6
(25.3)
Mean daily maximum °F (°C) 27.2
(−2.7) 		29.1
(−1.6) 		36.6
(2.6) 		41.9
(5.5) 		50.1
(10.1) 		57.9
(14.4) 		67.0
(19.4) 		65.9
(18.8) 		57.0
(13.9) 		43.7
(6.5) 		32.5
(0.3) 		25.5
(−3.6) 		44.5
(7.0)
Daily mean °F (°C) 17.1
(−8.3) 		17.1
(−8.3) 		23.6
(−4.7) 		28.8
(−1.8) 		37.6
(3.1) 		44.8
(7.1) 		51.6
(10.9) 		50.3
(10.2) 		43.4
(6.3) 		32.7
(0.4) 		22.5
(−5.3) 		15.6
(−9.1) 		32.1
(0.0)
Mean daily minimum °F (°C) 7.0
(−13.9) 		5.2
(−14.9) 		10.5
(−11.9) 		15.6
(−9.1) 		25.1
(−3.8) 		31.7
(−0.2) 		36.2
(2.3) 		34.7
(1.5) 		29.7
(−1.3) 		21.6
(−5.8) 		12.3
(−10.9) 		5.8
(−14.6) 		19.6
(−6.9)
Mean minimum °F (°C) −20.1
(−28.9) 		−23.3
(−30.7) 		−15.1
(−26.2) 		−6.1
(−21.2) 		5.9
(−14.5) 		23.0
(−5.0) 		29.5
(−1.4) 		26.8
(−2.9) 		16.7
(−8.5) 		−3.0
(−19.4) 		−14.4
(−25.8) 		−21.8
(−29.9) 		−31.9
(−35.5)
Record low °F (°C) −41
(−41) 		−40
(−40) 		−32
(−36) 		−24
(−31) 		−5
(−21) 		10
(−12) 		24
(−4) 		17
(−8) 		−1
(−18) 		−26
(−32) 		−37
(−38) 		−39
(−39) 		−41
(−41)
Average precipitation inches (mm) 2.90
(74) 		3.01
(76) 		3.44
(87) 		4.22
(107) 		4.51
(115) 		3.39
(86) 		1.84
(47) 		1.72
(44) 		2.01
(51) 		3.48
(88) 		3.12
(79) 		3.11
(79) 		36.75
(933)
Source 1: XMACIS2[7]
Source 2: NOAA (Precipitation)[8]

See also

References

  1. ^ a b c d "Boulder River". Geographic Names Information System. United States Geological Survey, United States Department of the Interior.
  2. ^ "A River Runs Through It Trivia at the IMDb". IMDb. Retrieved 2007-09-22.
  3. ^ "USGS Surface Water data for Montana: USGS Surface-Water Annual Statistics".
  4. ^ "USGS Surface Water data for Montana: USGS Surface-Water Annual Statistics".
  5. ^ "USGS Surface Water data for Montana: USGS Surface-Water Annual Statistics".
  6. ^ "Map of USFS Big Timber Ranger District". Retrieved 2007-09-22.
  7. ^ "xmACIS2". National Oceanic and Atmospheric Administration. Retrieved November 23, 2023.
  8. ^ "Placer Basin, Montana 1991-2020 Monthly Normals". Retrieved November 23, 2023.