The best time to hike in the Mission Mountains is between the beginning of July and October. Winter ends late in the high country and even in the beginning of July hikers will often find high passes and lakes snow-covered and wet. Snow starts to fly as early as October and hiking season is over by the end of the month. Winter recreation is best in the spring months. June is wet, but between February and May one can do some great winter camping, snowshoeing and skiing.