County Line Trailhead
Trailhead · Yosemite corridor
County Line Trailhead sits at 7,156 feet in the Yosemite corridor of the Sierra Nevada, offering high-elevation access to alpine terrain with typically lighter crowds than valley-floor alternatives.
Wind averages 7 mph but funnels stronger in afternoon hours, particularly when the lake basin heats. Morning calm is genuine; by midday, gusts can reach 17 mph. Temperature stays cool year-round, holding near freezing in spring and bottoming near 27 degrees in winter. Crowds cluster on weekends and opening weekends of Highway 120.
The 30-day rolling average wind stands at 7 mph, with temperatures averaging 38 degrees and a NoGo Score of 19. The last month has been stable by high-Sierra standards. The week ahead will track seasonal patterns: watch for afternoon wind pushes and post-storm clearing windows that typically drive midweek visits.
30 days back / 7 days forward
Today's score by factor
About County Line Trailhead
County Line Trailhead serves the high-Sierra corridor west of Mono County, accessed via Highway 120 from the east or CA-395 connections to the north. The trailhead sits at 7,156 feet, making it a natural staging point for hikers targeting alpine lakes and passes. Spring conditions here lag valley routes by two to three weeks; snowpack persistence and stream crossings dictate actual passability. The nearest fuel and supplies are in Lee Vining or Mammoth Lakes to the south. Parking fills quickly during peak weekends, especially the first week after Highway 120 opens to full traffic.
April and May bring the most variable conditions. Temperatures average 38 degrees over the last 30 days but swing from near freezing overnight to occasional 50-degree afternoons. Wind averages 7 mph but gusts to 17 mph are common, driven by pressure gradients across the Sierra crest. Crowding remains light by valley standards, averaging 20 over the rolling 30-day window. June through September sees warming, drier conditions and sharply rising foot traffic. October brings rapid cooling and the first hard freezes; November onward, snow and ice restrict access to winter-equipped parties.
County Line Trailhead suits hikers comfortable with exposure and unpredictable weather. Afternoon thunderstorms, sudden wind, and lingering snow patches require route finding and navigation skill. The low base popularity rating reflects its high-elevation position and alpine commitment; most visitors are self-sufficient backpackers and peak baggers rather than day-hike crowds. Park early or plan a weekday visit to avoid the lot fill that occurs Saturdays and opening-week Sundays. Bring layers; the 27-degree winter minimum and typical 38-degree spring average mean conditions can turn hostile fast.
Visitors pairing County Line with nearby options should consider Mono Lake roadside pullouts and Parker Lake Trail to the south for lower-elevation alternatives when snow blocks upper routes. The trailhead's elevation and latitude place it squarely in the transition zone between Valley and High Sierra conditions; timing a visit around the 7-day forecast wind and the NoGo Score trends (checking for scores under 25) significantly improves odds of clear, calm days.