Late-season mountain snow

Heavy late‑season snow this week buried high routes in the Sierra Nevada and Northern Rockies, leaving snow on many spring trails. (weather.gov) The National Weather Service issued winter storm warnings April 21–22 calling for 1–2 feet of snow above roughly 4,500–6,500 feet and ridgetop gusts as high as 90 mph. (forecast.weather.gov) Ski areas reported big April totals: Mammoth Mountain logged roughly 43 inches of new snow in one storm cycle, and resort operators extended the season after the dump. (tetongravity.com) (ktla.com) Forests and parks now list widespread spring snow on high trails; the National Park Service warns trails around 9,000 feet remain snow‑covered with depths from inches to several feet. (nps.gov) Avalanche centers issued heightened alerts after the storms: the Sierra Avalanche Center and the Eastern Sierra Avalanche Center reported unstable layers and warned backcountry travelers to expect elevated avalanche danger. (sierraavalanchecenter.org) (esavalanche.org) The late storms come after California’s Department of Water Resources reported a near‑zero April snow survey at Phillips Station earlier this month, underscoring how unusual the late buildup has been. (water.ca.gov) For hikers and scramblers this means real route changes: expect to carry traction and winter tools—microspikes or light crampons—and check local avalanche forecasts and recent observations before heading above treeline. (outdoorlife.com) (esavalanche.org) Forecasters say more Pacific systems could keep mountain snow showers in the pattern through the end of April, so high‑elevation routes are likely to remain wintery into spring—watch local NWS and avalanche‑center updates. (accuweather.com)