IMPROVED SEA BREEZE FORECASTING FOR BOSTON’S GENERAL EDWARD LAWRENCE LOGAN INTERNATIONAL AIRPORT Jennifer Thorp Judd Gregg Meteorology Institute Plymouth State University Plymouth, NH Scott Reynolds NOAA National Weather Service Center Weather Service Unit Nashua, NH This study adapts the method of predicting sea-breeze events developed by Miller and Keim (2003) to Logan International Airport in Boston, Massachusetts (KBOS). A five-year dataset of hourly KBOS surface observations (2001-2005) was used to identify 565 days when the sea breeze occurred or was likely to occur at the airport. These days were classified into sea-breeze, marginal, or non-sea-breeze events. Sea-breeze events were further classified into fast and slow transitions, with a fast transition identified with a wind shift taking one hour or less, and a slow transition identified with a wind shift taking two hours or more. Morning United States surface analyses for each event were classified using the seven synoptic classes developed by Miller and Keim (2003), and statistics were developed to evaluate the distribution of synoptic classes amongst the different types of events and various seasons. Composite surface analyses of the different synoptic classes and types of events were then developed. There were significant differences between the composites of each event type within a synoptic class. The results of this study were then compared to those of Miller and Keim. The next stages of research will be to further examine the mesoscale pressure and isentropic gradients associated with all types of events and to investigate the effect of coastline shape upon the sea breeze. The dataset will be increased to nine and a half years and research regarding the interaction of the sea breeze with warm season convection will be presented using radar data. The second part of the discussion will focus on usage of the Thorp et al technique in an operational environment. The Center Weather Service Unit (CWSU), located at the Boston Air Route Traffic Control Center (ARTCC) in Nashua NH, prepares a daily, internal sea breeze forecast for KBOS, and uses that information in briefings given to Traffic Management personnel at the Boston ARTCC, Terminal Radar Approach Control facility in Merrimack, NH, Boston Air Traffic Control Tower, and during forecast collaboration with the NWS Taunton forecast office. This research was funded under COMET Partners Project S06-58394. PRESENTERS’ BIOs Ms. Thorp graduated from Plymouth State University in 2007 with a Bachelor of Science in Meteorology and a minor in Technical Mathematics. She interned at Weather Services International during the summer of 2007. Jen is currently a Master of Science candidate in Applied Meteorology at Plymouth State University with an expected completion date of December 2008. Mr. Reynolds is currently the Meteorologist-in-Charge at the National Weather Service’s Center Weather Service Unit in Nashua, NH. He received a Bachelor of Science degree in Meteorology from Plymouth State University in 1989. His career with the National Weather Service has included stops as a Student Trainee in Albany NY, Meteorologist Intern in Burlington VT, forecaster in Charleston WV, and Senior Forecaster at the Upton (Long Island) NY office. He returned to New England in 2005 as the MIC in Nashua. Scott lives in Nashua with his wife, Andrea, and their two children, Jeremy and Allison. .