Weir Lake
Lake · 9,593 ft · Eastern Sierra corridor
Weir Lake sits at 9593 feet in the Eastern Sierra, a high-alpine reservoir fed by snowmelt and ringed by granite. Wind dominates the afternoon; morning calm is the window.
Weir Lake funnels wind off the high desert by mid-afternoon, with gusts reaching 38 mph on exposed days. Morning flatness typically holds until 10 a.m. The 30-day average wind of 11 mph masks swings from glassy to punchy. Water temperature reflects the elevation; even in summer, hypothermia is a real risk.
Over the last 30 days, Weir Lake has averaged a NoGo Score of 36, with temperatures holding at 28 degrees Fahrenheit and wind averaging 11 mph. The range has been wide: lows of 4 and peaks near 65, reflecting spring's volatility at this elevation. The week ahead will show whether the pattern softens or if afternoon winds continue to dominate the lake surface.
30 days back / 7 days forward
Today's score by factor
About Weir Lake
Weir Lake is a glacially-carved alpine reservoir in the Eastern Sierra corridor of California's Sierra Nevada, positioned at 9593 feet on the west flank of the range. The lake drains into the Owens River system and sits roughly 3 hours from Mammoth Lakes via Highway 395 and local forest roads. Access requires a high-clearance vehicle and willingness to navigate washboard and seasonal gates; early season and late autumn often close approach routes. The nearest reliable fuel and services are in Mammoth Lakes to the south; Bishop to the southeast offers additional supplies and lodging. Weir Lake is not a destination for casual drive-to access; it demands planning and local knowledge.
Conditions at Weir Lake track elevation and exposure with harsh consistency. The 30-day average temperature of 28 degrees Fahrenheit is typical for a 9593-foot alpine lake in spring; winter can drop to 11 degrees, while brief summer peaks reach 41 degrees. Wind is the dominant constraint. The 30-day average of 11 mph conceals violent afternoon swings; maximum gusts in the rolling window hit 38 mph, and afternoons on clear days are routinely unpaddle-able. Crowding remains light year-round (30-day average of 3), a reflection of the remote access and alpine commitment required. Spring and early summer bring rapid snowmelt and peak runoff; late September and early October offer the most stable weather window before early-season storms return.
Weir Lake suits experienced backcountry paddlers, anglers willing to hike, and high-elevation mountaineers. The lake is too exposed and cold for recreational swimmers or families. Paddlers must plan for morning-only windows and carry heavy layers; the wind can pin boats or sweep inexperienced users offshore in minutes. Avalanche terrain surrounds the approach and basin; late-winter and spring require careful assessment of slope stability and rapid-runoff hazards. Anglers should expect difficult access and sparse catches; the remoteness is the draw, not the productivity. Parking is limited and informal; arrive early in the day or accept hiking from the roadhead. Early-season (late spring through July) can mean crossing snowfields and fording swollen creeks.
Nearby alternatives include Mammoth Lake and June Lake, both lower and more accessible but significantly more crowded. The Inyo National Forest surrounding Weir Lake offers dozens of smaller alpine tarns at comparable or slightly lower elevations with better shelter from wind. Convict Lake, an hour south, provides similar mountain-lake character with more reliable road access and established facilities. For those committed to the Eastern Sierra high country, Weir Lake delivers isolation and raw alpine character; it is not a warm-up destination or a Plan B. The avalanche center serving the region is ESAC; winter and spring visitors must check conditions and understand terrain-specific hazards before committing to approach.