• Source: Witches Tower (Washington)
    • Witches Tower is an 8,566-foot (2,611-metre) granite summit located 10 mi (16 km) southwest of Leavenworth in Chelan County of Washington state. Witches Tower is part of The Enchantments within the Alpine Lakes Wilderness, and is set on land managed by the Okanogan–Wenatchee National Forest. It belongs to the Stuart Range which is subset of the Wenatchee Mountains. Witches Tower is situated 0.8 mi (1.3 km) northwest of Little Annapurna, and 0.4 mi (0.64 km) east-southeast of Dragontail Peak, which is its nearest higher neighbor. Witches Tower is surrounded by remnants of Snow Creek Glacier. Precipitation runoff drains into tributaries of the Wenatchee River.


      Climate


      Weather fronts originating in the Pacific Ocean travel east toward the Cascade Mountains. As fronts approach, they are forced upward by the peaks (orographic lift), causing them to drop their moisture in the form of rain or snow onto the Cascades. As a result, the Cascades experience high precipitation, especially during the winter months in the form of snowfall. Because of maritime influence, snow tends to be wet and heavy, resulting in avalanche danger. 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.


      Geology


      The Alpine Lakes Wilderness features some of the most rugged topography in the Cascade Range with craggy peaks and ridges, deep glacial valleys, and granite walls spotted with over 700 mountain lakes. 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 history of the formation of the Cascade Mountains dates back millions of years ago to the late Eocene Epoch. With the North American Plate overriding the Pacific Plate, episodes of volcanic igneous activity persisted. In addition, small fragments of the oceanic and continental lithosphere called terranes created the North Cascades about 50 million years ago.
      During the Pleistocene period dating back over two million years ago, glaciation advancing and retreating repeatedly scoured the landscape leaving deposits of rock debris. The last glacial retreat in the Alpine Lakes area began about 14,000 years ago and was north of the Canada–US border by 10,000 years ago. The U-shaped cross section of the river valleys is a result of that 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 Alpine Lakes Wilderness area.


      See also


      List of peaks of the Alpine Lakes Wilderness


      Gallery

















      References




      External links


      Witches Tower weather forecast: National Weather Service
      Alpine Lakes Wilderness (Wenatchee National Forest) U.S. Forest Service

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