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The Needles is an 8,160-foot (2,490-metre) granite mountain located in Okanogan County in Washington state. It is part of the Okanogan Range which is a sub-range of the North Cascades Range.[1] The Needles is situated on land administered by the Okanogan–Wenatchee National Forest. The nearest higher peak is Tower Mountain, 2.26 miles (3.64 km) to the southwest.[1]

The Needles
The Needles seen from North Cascades Highway
Highest point
Elevation8,160 ft (2,490 m)[1]
Prominence1,759 ft (536 m)[1]
Coordinates48°35′59″N 120°39′27″W[1]
Geography
The Needles
Washington, U.S.
Parent rangeNorth Cascades
Climbing
First ascentHelmy Beckey, Larry Strathdee in 1944 [2]
Easiest routeClimb

Climate


The Needles is located in the marine west coast climate zone of western North America.[2] Most weather fronts originate in the Pacific Ocean, and travel northeast toward the Cascade Mountains.

The Needles from Wallaby Peak
The Needles from Wallaby Peak

As fronts approach the North Cascades, they are forced upward by the peaks of the Cascade Range, causing them to drop their moisture in the form of rain or snowfall onto the Cascades (Orographic lift). As a result, the west side of the North Cascades experiences high precipitation, especially during the winter months in the form of snowfall. During winter months, weather is usually cloudy, but, due to high pressure systems over the Pacific Ocean that intensify during summer months, there is often little or no cloud cover during the summer.[3] Because of maritime influence, snow tends to be wet and heavy, resulting in high avalanche danger.[3]


Geology


The North Cascades features some of the most rugged topography in the Cascade Range with craggy peaks, ridges, and deep glacial valleys. Geological events occurring many years ago created the diverse topography and drastic elevation changes over the Cascade Range leading to the various climate differences.

The Needles seen from Slate Peak
The Needles seen from Slate Peak

The history of the formation of the Cascade Mountains dates back millions of years ago to the late Eocene Epoch.[4] With the North American Plate overriding the Pacific Plate, episodes of volcanic igneous activity persisted.[4] In addition, small fragments of the oceanic and continental lithosphere called terranes created the North Cascades about 50 million years ago.[4] The Needles is carved mostly from granite of the Golden Horn batholith.

The Needles from the PCT
The Needles from the PCT

During the Pleistocene period dating back over two million years ago, glaciation advancing and retreating repeatedly scoured the landscape leaving deposits of rock debris.[4] The "U"-shaped cross section of the river valleys are a result of recent glaciation. Uplift and faulting in combination with glaciation have been the dominant processes which have created the tall peaks and deep valleys of the North Cascades area.


See also



References


  1. "The Needles, Washington". Peakbagger.com.
  2. Beckey, Fred W. Cascade Alpine Guide, Climbing and High Routes. Seattle, WA: Mountaineers Books, 2008.
  3. Beckey, p. 16
  4. Kruckeberg, Arthur (1991). The Natural History of Puget Sound Country. University of Washington Press.





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