Cox Col
Peak · 13,060 ft · Mammoth Lakes corridor
Cox Col is a 13,060-foot pass in the Mammoth Lakes corridor's high Sierra, exposed to substantial afternoon wind and accessible primarily to experienced mountaineers and ski tourers.
Wind accelerates dramatically after mid-morning, funneling through the pass as thermal circulation strengthens. The 30-day average wind of 13 mph masks gusts exceeding 30 mph by afternoon. Temperatures hover near 18 degrees Fahrenheit on average; snow-covered slopes dominate late spring and early summer. Morning calm is the only reliable window.
Over the past 30 days, the average NoGo Score of 37 reflects marginal conditions driven by consistent wind. Gusts have reached 39 mph, and average wind sits at 13 mph. The week ahead continues this pattern: expect stronger afternoon winds, temperatures in the low teens, and sparse crowds below 2 per day average. Head early or expect a challenging afternoon.
30 days back / 7 days forward
Today's score by factor
About Cox Col
Cox Col sits at 13,060 feet in the Sierra Nevada's Mammoth Lakes corridor, straddling high alpine terrain east of the crest. Access requires technical mountaineering or ski-touring skill; there is no maintained trail. The nearest road hub is Mammoth Lakes town to the south. Approach routes vary depending on snowpack and season: some parties climb from the north via the Long Lakes basin, others from the south via drainage systems off the main crest. This is not a casual day-hike destination. Elevation, avalanche terrain, and sustained wind exposure demand route-finding ability, navigation proficiency, and avalanche awareness.
Winter and spring dominate the use calendar. Snow persists at the pass through late spring; by mid-summer, rock and talus replace continuous snowpack. The 30-day average temperature of 18 degrees Fahrenheit and maximum wind speed of 39 mph reflect conditions typical of late April through May. Summer temperatures climb into the upper 20s to low 30s; afternoon thunderstorms develop frequently by mid-July. Autumn offers stable weather but shorter daylight. Winter ascents are rare and carry significant avalanche and exposure risk. Most successful parties target the transition window between spring snowmelt and early-summer thunderstorm onset.
Cox Col suits ski mountaineers and alpine climbers comfortable with exposure, self-rescue, and avalanche assessment. Parties typically ascend early, depart by early afternoon, and carry mountaineering or ski descent equipment. Water sources are limited; much of the approach crosses snowfields or barren rock. Cell reception is unreliable. The average crowding metric of 2 reflects extremely low use; solitude is assured, but rescue response time is substantial. Parties must be fully self-sufficient in navigation, first aid, and emergency communication. Avalanche terrain is present on multiple aspects; assess snowpack stability and terrain traps before committing to slopes.
Nearby peaks in the Mammoth corridor include Mammoth Mountain to the southeast and numerous 12,000-plus-foot summits accessible from Highway 395. Norman Clyde Peak, Darwin, and peaks in the Sierra Crest high country offer comparable elevation and exposure but different drainage systems and access logistics. Cox Col's defining character is its isolation and wind tunneling; it is less trafficked and more exposed than roadside trailhead peaks. Visitors considering Cox Col should confirm avalanche forecasts from ESAC and expect to navigate entirely off-trail in significant avalanche terrain.