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 (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.