Mount St. Helens was once again into it's dome-building phase after the October eruptions. As I
drove higher up into the mountains, a large ash cloud billowed up from the crater. I parked at
the Johnson Ridge Observatory, the closet point we were allowed to drive to the mountain. While
visiting inside the observatory, one of the rangers on duty gave a presentation from the outside
balcony. I learned that the ash plume was caused by a 16 cubic meter chunk of the dome that had
broken off and dropped down into the crater. Just before I left, another piece had broken off and
fallen to the crater floor.