Some summers the passes in the Sierra Nevada range open early and other years they open late. It all depends on how much snow accumulates during the winter and into the spring. A late snowstorm can set things back even further, but every year is a little different in one way or another. The Sierra Nevada saw a lot of snow during the early months of 2019 and so passes stayed buried in snow later than normal. Many trailheads will not be accessible until July this year. For hikers doing the section of the Pacific Crest Trail that goes over Forester Pass, the way will be particularly difficult with snow on the pass well into August. It may even be the case that this year Forester Pass never gets completely snow free. Of course, snow covered passes are not the only issue. Streams which normally flow gently may become raging torrents for an extended period of time as the massive amount of snow melts. However, there's no point in complaining, excessive snow is undoubtedly preferable to a drought, especially in the crowded state of California!