Atmospheric Icing Climatologies of Two New England Mountains

Abstract

The atmospheric icing climatologies of two New England mountaintops with different elevations are compared: Mount Mansfield in northern Vermont and Mount Washington in New Hampshire. Atmospheric icing, as measured with Rosemount ice detectors, is twice as frequent on Mount Washington with about 12 to 20 times greater intensities and 25 to 50 times more accretion as on Mount Mansfield. Most of Mount Mansfield icing events are of low intensity, with periods between icing events averaging 35 to 45 hours on both peaks. Return intervals of ice events by length, intensity, and accretion amount are tabled. Approximately one-half of all severe icing on the two peaks occurs during and immediately after cold front passages. Icing is most intense when lows are about 450 km to the east and high pressure centers are more than about 450 km distant. Prolonged accretion periods occur when coastal and inland storms merge or follow closely.