Types of Synoptic Storms that Drive High Storm Surge in Boston Harbor

Daily and hourly atmospheric circulation data are examined during high storm surge events in Boston Harbor to determine what synoptic-scale patterns of wind structure and evolution over time are most conducive to local high surge events. Events associated with tropical cyclone activity are excluded, to focus on the role of synoptic storms. While tropical cyclones are associated with several of the largest surge events, the generally slower movement of synoptic storms results in a greater likelihood of the peak storm surge aligning with high tide, so that synoptic storms are an important contributor to local high surge events. K-means clustering is used to identify five distinct patterns in winds associated with high surges. Lead-lag analysis is applied to each pattern to characterize the life cycle, track, and relationship to larger-scale jet stream anomalies. The most prominent pattern is a classic, relatively slow moving Nor’easter with a coastal track but several other distinct storm types are obtained.