Sentinel Peak (Jefferson County, Washington)


Sentinel Peak is a mountain summit located in the Olympic Mountains, in Jefferson County of Washington state. Rising in the center of Olympic National Park, its nearest higher peak is Mount Fromme, to the northwest. Sentinels Sister is a lower companion summit situated to the southwest. The two peaks stand as sentinels above the Dosewalips Valley and Hayden Pass, and were possibly named by an early expedition of the Seattle Mountaineers. Precipitation runoff from the peak drains to Hood Canal via the Dosewallips River.

Climate

Sentinel Peak is located in the marine west coast climate zone of western North America. Most weather fronts originate in the Pacific Ocean, and travel northeast toward the Olympic Mountains. As fronts approach, they are forced upward by the peaks of the Olympic Range, causing them to drop their moisture in the form of rain or snowfall. As a result, the Olympics experience 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. The best months for climbing in terms of favorable weather are June through September.

Geology

The Olympic Mountains are composed of obducted clastic wedge material and oceanic crust, primarily Eocene sandstone, turbidite, and basaltic oceanic crust. The mountains were sculpted during the Pleistocene era by erosion and glaciers advancing and retreating multiple times.