Geophysical Research Letters

An investigation of thundersnow and deep snow accumulations



[1] A comparison of 30 years of hourly surface weather observations (1960–1991) from first-order stations and 24-hour snowfall data from climate network stations over the upper Midwestern United States reveals an indirect association between the relatively rare occurrence of thundersnow (<1 event yr−1 in this dataset) and the accumulation of significant 24-hour snowfall (>15 cm) in 19 of 22 cases identified. Although no direct relationship is found between the location of thundersnow and the deepest 24-hour snow totals, significant snow accumulations frequently occurred in proximity (<1° latitude) to thundersnow events. The presence of thundersnow tended to indicate a parent extratropical cyclone capable of producing significant snowfall totals; should thundersnow be anticipated, the operational meteorologist can have much greater confidence in forecasting deeper snow totals.