Northeast wind in the Gulf of Maine is under-forecasted regularly by both numerical weather prediction (NWP) models and human forecasters. These wind events cause a significant hazard to coastal marine and aviation interests. Vertical wind shear, as well as high waves and coastal flooding, are the primary threats of these enhanced northeast winds. One of many significant events occurred in May 2005, when a northeast wind event, poorly-forecasted by NWP and human forecasters, enveloped the coastline with very high winds, waves and flooding. This event alone caused over $1 million USD in damages to rescue boats, yachts and docks.

Using HPC surface analyses and NARR dataset composites, synoptic-scale evolution for 48, 24 and 12 hours prior to event onset were determined for four synoptic classifications of events. Evolution is shown using composite sea-level pressure and individual case pressure center variability. Event duration stratified by synoptic class has also been studied. Significant steps have been made to developing an improved forecasting technique for these events based on the above. Pattern recognition based on event evolution on both scales, as well as knowledge of model biases in northeast flow, will aid human forecasters in accurately predicting these events in the future for public and private interests along the coastline.