Spire Pass
Peak · 12,418 ft · Mammoth Lakes corridor
Spire Pass is a 12,418-foot alpine pass in the Mammoth Lakes corridor of California's Sierra Nevada. Wind funnels from the east and west across the crest; shelter is sparse.
Wind dominates here. The 30-day average is 13 mph, with gusts to 39 mph common during afternoon and evening hours. Morning calm windows close by mid-morning on most days. Snow lingers into early summer; exposed ridges shed quickly, but north-facing drainages hold patches through late spring.
Over the past 30 days, Spire Pass has averaged a NoGo Score of 37 with temperatures near 18F and winds averaging 13 mph. The week ahead will track seasonal wind and melt patterns typical for late spring in the high Sierra. Check recent avalanche bulletins from ESAC before any approach that crosses steep terrain or requires boot-packing on snow.
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About Spire Pass
Spire Pass sits on the crest of the Sierra, east of the Mammoth Lakes basin and west of the high desert plateau. Access typically runs from the Mammoth Lakes area via Highway 203 inland, then on to trailheads near Lake George or trails rising from the Lakes Basin. The pass itself is a transitional crossing between the wetter west slope and the drier east slope; it marks the boundary between two distinct precipitation and snowmelt regimes. Winter and spring approach this location only on foot or skis; no road crosses the crest here. The nearest paved towns are Mammoth Lakes to the west and Lone Pine to the southeast, each roughly an hour's drive from the nearest trailhead.
Temperature at the pass averages 18F over the rolling 30-day window, with seasonal extremes from 4F in winter to 31F in mid-summer. Wind is the defining constraint. The 30-day average wind speed is 13 mph, but max gusts reach 39 mph; afternoon and evening intensification is typical as solar heating drives pressure gradients. Crowding remains light (2.0 average), since the pass sits off major tourist highways and requires a solid day hike or backpack commitment. Late spring (April and May) brings rapid snowmelt and potential instability on steep north and east-facing slopes; ESAC avalanche forecasts are essential reading before any approach through avalanche terrain.
Spire Pass appeals to experienced backcountry hikers and skiers seeking high-altitude crossings with minimal infrastructure. The pass itself offers no shelter, water, or camping; visitors must be self-sufficient for weather and emergencies. Late-morning wind ramps are predictable enough that experienced parties plan early starts and descents before 2 p.m. Parking at trailheads fills slowly outside peak weekends; a midweek Tuesday start avoids congestion entirely. Summer (late July through August) sees warmer temperatures and dry snow/bare rock, shortening the avalanche-prone window but introducing afternoon thunderstorm risk. Winter crossing demands mountaineering skills, proper gear, and avalanche training.
Nearby alternatives include Kearsarge Pass to the south, which offers similar high-Sierra character but better-established trailhead infrastructure. Mammoth Crest to the north provides gentler ridgeline travel with comparable wind exposure. The Mammoth corridor as a whole spans from the Minarets in the north to the Crestview peaks in the south; Spire Pass sits centrally and connects the Lakes Basin approach to east-slope descents. Visitors combining multiple passes over several days should plan for the 39 mph max wind events and carry reserves of water and shelter even on clear forecasts.