Slate Peak is a mountain summit located on the shared border between

Okanogan County Okanogan County () is a county located in the U.S. state of Washington along the Canada–U.S. border. As of the 2020 census, the population was 42,104. The county seat is Okanogan, while the largest city is Omak. Its area is the largest i ...

and

Whatcom County Whatcom County is a county located in the northwestern corner of the U.S. state of Washington, bordered by the Canadian Lower Mainland (the Metro Vancouver and Fraser Valley Regional Districts of British Columbia) to the north, Okanogan Co ...

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered o ...

state. It is part of the

Okanogan Range The Okanagan Range or Okanogan Range is a small subrange of the Cascade Range straddling the border between British Columbia and Washington south of the Similkameen River on the inland side of the range. The range is the northeasternmost extremity ...

, which is a sub-range of the

North Cascades The North Cascades are a section of the Cascade Range of western North America. They span the border between the Canadian province of British Columbia and the U.S. state of Washington and are officially named in the U.S. and Canada as the C ...

. The mountain is situated northwest of Mazama, on the boundary line of the

Pasayten Wilderness The Pasayten Wilderness is a protected area located within Okanogan–Wenatchee National Forest and Mount Baker National Forest in Washington state, centered on the Three Forks () of the Pasayten River, a tributary of the Similkameen River. ...

, on land managed by the

Okanogan–Wenatchee National Forest The Okanogan National Forest is a U.S. National Forest located in Okanogan County in north-central Washington, United States. The forest is bordered on the north by British Columbia, on the east by Colville National Forest, on the south by the ...

. The peak has the distinction of having the highest road in Washington, as well as the highest fire lookout. Although the narrow one-lane white-knuckle road reaches the summit of the mountain, the Forest Service gated it to vehicles, which necessitates walking the final few hundred yards. Additionally, the

Pacific Crest Trail The Pacific Crest Trail (PCT), officially designated as the Pacific Crest National Scenic Trail, is a long-distance hiking and equestrian trail closely aligned with the highest portion of the Cascade and Sierra Nevada mountain ranges, which lie ...

traverses the west slope of the peak, and the West Fork Pasayten Trail traverses the eastern slope. The nearest higher peak is Devils Peak, to the north. Precipitation

runoff Runoff, run-off or RUNOFF may refer to: * RUNOFF, the first computer text-formatting program * Runoff or run-off, another name for bleed, printing that lies beyond the edges to which a printed sheet is trimmed * Runoff or run-off, a stock market ...

from Slate Peak drains east into Pasayten River, or west into Slate Creek, which is in the

Skagit River The Skagit River ( ) is a river in southwestern British Columbia in Canada and northwestern Washington in the United States, approximately 150 mi (240 km) long. The river and its tributaries drain an area of 1.7 million acres (690,000 ...

drainage basin.

Slate Peak Fire Lookout

The fire lookout tower was originally constructed as a gable-roof cupola in 1924. In 1956 the Air Force leveled the mountain summit by removing 40 feet from the top of the peak (as well as the lookout) in order to install a radar station, which was never built. The present lookout sits atop a 41-foot tall tower which is maintained for emergency use. The Slate Peak Lookout was added to the

National Historic Lookout Register The National Historic Lookout Register is a program administered by the United States Forest Service, the Forest Fire Lookout Association The Forest Fire Lookout Association (FFLA) is a group dedicated to the worldwide research and restoration ...

on November 4, 2000. On a clear day, visitors can see Silver Star Mountain,

The Needles The Needles is a row of three stacks of chalk that rise about out of the sea off the western extremity of the Isle of Wight in the English Channel, United Kingdom, close to Alum Bay and Scratchell's Bay, and part of Totland, the wester ...

, Tower Mountain,

Golden Horn The Golden Horn ( tr, Altın Boynuz or ''Haliç''; grc, Χρυσόκερας, ''Chrysókeras''; la, Sinus Ceratinus) is a major urban waterway and the primary inlet of the Bosphorus in Istanbul, Turkey. As a natural estuary that connects with t ...

Azurite Peak Azurite Peak is an double-summit mountain located at the common boundary point of Okanogan County, Skagit County, and Whatcom County in Washington state. It is part of the Okanogan Range which is a sub-range of the North Cascades Range. Azurit ...

Mount Ballard Mount Ballard, with an elevation of is located in Cochise County, Arizona, about west of Bisbee. See also * List of mountains and hills of Arizona by height References {{Mountains of Arizona Landforms of Cochise County, Arizona ...

Jack Mountain Jack Mountain is the 17th highest mountain in Washington state. It is one of the 10 non-volcanic peaks in Washington State over . It towers dramatically over the south end of Ross Lake, rising above the lakeshore in only . Nohokomeen Glacier ...

Crater Mountain Crater Mountain is an mountain summit located in the North Cascades of Washington state. It is the 29th highest mountain in the Pasayten Wilderness. The Jerry Glacier resides in the cirque on the upper north slopes of the mountain. The crate ...

, Monument Peak, Robinson Mountain, and many others from the tower.

Climate

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 ...

s originate in the

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

, 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 the North Cascades, ...

. 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 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 higher precipitation than the east side, 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.Beckey, Fred W. Cascade Alpine Guide, Climbing and High Routes. Seattle, WA: Mountaineers Books, 2008. July through September are the best months to visit in terms of favorable weather and the Forest Service access road being open for the season, however, smoke from distant wildfires may potentially reduce visibility, and smoky summer conditions have been increasing with climate change.

Geology

The North Cascades features some of the most rugged topography in the Cascade Range with craggy peaks, spires, 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 ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...

Epoch. With the

North American Plate The North American Plate is a tectonic plate covering most of North America, Cuba, the Bahamas, extreme northeastern Asia, and parts of Iceland and the Azores. With an area of , it is the Earth's second largest tectonic plate, behind the Pacifi ...

overriding the

Pacific Plate The Pacific Plate is an oceanic tectonic plate that lies beneath the Pacific Ocean. At , it is the largest tectonic plate. The plate first came into existence 190 million years ago, at the triple junction between the Farallon, Phoenix, and I ...

, 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 Oceanic is an unincorporated set ...

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 portion of the upper mantle that behaves elastically on time scales of up to thousands of years or ...

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 ow ...

s created the

about 50 million years ago. During the

Pleistocene The Pleistocene ( , often referred to as the '' Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed ...

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 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.

Gallery

File:HART PASS - SLATE PEAK (07-19-2022) Okanogan Co, WA.jpg, Slate Peak File:View from Slate Peak lookout tower looking west.jpg, A clear view from Slate Peak's tower looking west to Jack Mountain File:South panorama from Slate Peak.jpg, Panorama looking south from Slate Peak. Left to right: Silver Star, The Needles, Tower Mountain, Golden Horn File:The North Cascades- Slate Peak.jpg, Slate Peak File:Gated road to Slate Peak.jpg, Gated road to Slate Peak

References

External links

* Weather forecast
Slate Peak
* Slate Peak Trailhead
US Forest Service
* Slate Peak aerial photo
PBase
{{Geographic Location 2 , Center = Slate Peak , North =

Pasayten Peak Pasayten Peak is a pyramidal-shaped mountain summit located in western Okanogan County in Washington state. It is part of the Okanogan Range which is a sub-range of the North Cascades. The mountain is situated in the Pasayten Wilderness, on la ...

, Northeast = Haystack Mountain , East = Devils Peak , Southeast = Slate Pass , South = Harts Pass , Southwest = Tatie Peak , West = Slate Creek , Northwest = Tamarack Peak North Cascades Mountains of Washington (state) Mountains of Okanogan County, Washington Mountains of Whatcom County, Washington Cascade Range Fire lookout towers in Washington (state) North American 2000 m summits