Colonial Peak is a mountain in the

North Cascades The North Cascades are a section of the Cascade Range of western North America. They span the border between the Provinces and territories of Canada, Canadian province of British Columbia and the U.S. state of Washington (state), Washington and ...

Washington Washington most commonly refers to: * George Washington (1732–1799), the first president of the United States * Washington (state), a state in the Pacific Northwest of the United States * Washington, D.C., the capital of the United States ** A ...

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

. It rises steeply from the southwest bank of Thunder Arm of Diablo Lake, one of the artificial reservoirs on the

Skagit River The Skagit River ( ) is a river in southwestern British Columbia in Canada and northwestern Washington (state), Washington in the United States, approximately 150 mi (240 km) long. The river and its tributaries drain an area of 1.7&nbs ...

. It is part of a group of peaks that form the northern end of a chain running south through prized

climbing Climbing is the activity of using one's hands, feet, or other parts of the body to ascend a steep topographical object that can range from the world's tallest mountains (e.g. the eight thousanders) to small boulders. Climbing is done for locom ...

destinations such as

Eldorado Peak Eldorado Peak is a peak, and is the 25th highest peak in Washington. The mountain is located in the North Cascades of Washington, approximately east of Concrete. It is located in North Cascades National Park at the head of Marble Creek and j ...

Forbidden Peak Forbidden Peak is an glacial horn located in North Cascades National Park, in Skagit County of Washington state. It is part of the North Cascades and is located near Cascade Pass. Forbidden Peak features a rock climbing route named '' Wes ...

, and

Goode Mountain Goode Mountain is one of the major peaks of the North Cascades in the U.S. state of Washington (state), Washington. Named for topographer Richard Urquhart Goode of the United States Geological Survey, it is the highest peak located in North Casca ...

. Colonial Peak takes its name from the Colonial mining claim on its slopes. Like many North Cascade peaks, Colonial Peak is more notable for its large, steep rise above local

terrain Terrain (), alternatively relief or topographical relief, is the dimension and shape of a given surface of land. In physical geography, terrain is the lay of the land. This is usually expressed in terms of the elevation, slope, and orientati ...

than for its absolute elevation. For example, it rises above Thunder Arm in only . Its rise over the Skagit river on the northwest is even greater, but not as steep. Colonial Peak was first climbed on July 31, 1931, by William Degenhardt and Herbert Strandberg of the Seattle Mountaineers. The standard route is the West Ridge, accessed from Colonial Glacier; the approach is via the Pyramid Lake Trail, starting from near

Diablo Dam Diablo Dam is one of three dams along the upper Skagit River in Whatcom County, Washington and part of the Skagit River Hydroelectric Project that supplies Seattle with some of its power needs. The dam was built in Diablo Canyon, a gorge of solid ...

on the

North Cascades Highway North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating direction or geography. Etymology The word ''north'' is ...

Climate

Colonial Peak is located in the

marine west coast An oceanic climate, also known as a marine climate or maritime climate, is the temperate climate sub-type in Köppen classification represented as ''Cfb'', typical of west coasts in higher middle latitudes of continents, generally featuring co ...

climate zone of western

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

. Most

weather front A weather front is a boundary separating air masses for which several characteristics differ, such as air density, wind, temperature, and humidity. Disturbed and unstable weather due to these differences often arises along the boundary. For ins ...

s originate in the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...

, and travel northeast toward the

Cascade Mountains The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as many of those in the ...

. As fronts approach the

, they are forced upward by the peaks of the Cascade Range, causing them to drop their moisture in the form of

rain Rain is a form of precipitation where water drop (liquid), droplets that have condensation, condensed from Water vapor#In Earth's atmosphere, atmospheric water vapor fall under gravity. Rain is a major component of the water cycle and is res ...

snowfall Snow consists of individual ice crystals that grow while suspended in the atmosphere—usually within clouds—and then fall, accumulating on the ground where they undergo further changes. It consists of frozen crystalline water througho ...

onto the Cascades (

Orographic lift Orographic lift occurs when an air mass is forced from a low elevation to a higher elevation as it moves over rising terrain. As the air mass gains altitude it quickly cools down adiabatically, which can raise the relative humidity to 100% and cr ...

). 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. Because of maritime influence, snow tends to be wet and heavy, resulting in high

avalanche An avalanche is a rapid flow of snow down a Grade (slope), slope, such as a hill or mountain. Avalanches can be triggered spontaneously, by factors such as increased precipitation or snowpack weakening, or by external means such as humans, othe ...

danger.

Geology

The North Cascades features some of the most rugged topography in the

Cascade Range The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington (state), Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as m ...

with craggy peaks, ridges, and deep

glacial valley U-shaped valleys, also called trough valleys or glacial troughs, are formed by the process of glaciation. They are characteristic of mountain glaciation in particular. They have a characteristic U shape in cross-section, with steep, straight s ...

s. 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 The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...

Epoch. With the North American Plate overriding the Pacific Plate, episodes of volcanic igneous activity persisted. In addition, small fragments of the

oceanic Oceanic may refer to: *Of or relating to the ocean *Of or relating to Oceania **Oceanic climate **Oceanic languages **Oceanic person or people, also called "Pacific Islander(s)" Places * Oceanic, British Columbia, a settlement on Smith Island, ...

and

continental lithosphere A lithosphere () is the rigid, outermost rocky shell of a terrestrial planet or natural satellite. On Earth, it is composed of the crust and the lithospheric mantle, the topmost portion of the upper mantle that behaves elastically on time sc ...

called

terrane In geology, a terrane (; in full, a tectonostratigraphic terrane) is a crust fragment formed on a tectonic plate (or broken off from it) and accreted or " sutured" to crust lying on another plate. The crustal block or fragment preserves its d ...

s created the

about 50 million years ago. During the

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

period dating back over two million years ago, glaciation advancing and retreating repeatedly scoured the landscape leaving deposits of rock debris. The U-shaped cross section of the river valleys is 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. Colonial Peak from Ruby Mountain

References

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External links

North Cascades National Park
National Park Service * Colonial Peak weather
Mountain Forecast
Mountains of Whatcom County, Washington Mountains of Washington (state)