Toward a Further Understanding and Improved Forecasting of Coastal Quasi-linear Convective Systems

There has been a considerable amount of study about thunderstorm complexes and how they intensify and sustain themselves over the continental United States. Less research has been conducted on how those complexes interact with the cooler, more stable air of the marine atmospheric boundary layer along coastal regions. This study will consist of numerical model simulations of thunderstorms as they move offshore. The importance of this research lies in the fact that these types of thunderstorm complexes contribute to a significant portion of severe weather reports in heavily populated coastal areas of the Mid-Atlantic and Northeastern United States. The main outcome of this project will be an understanding of the factors that lead to the decay of the thunderstorms near the shoreline, survival of the storms until just offshore, or whether the systems can sustain themselves well out into the ocean. The lead researcher will interact with the National Weather Service and other government and private entities to ensure that the knowledge is transferred to decision-makers. This project will also contribute to the future scientific workforce through the training of a graduate student.

The researcher plans to improve understanding and prediction of evolving quasi-linear convective systems (QLCS) as they move offshore from inland regions and interact with the marine atmospheric boundary layer (MABL) over coastal waters. The project will systematically study the storm scale physical processes through idealized numerical modeling using a cloud resolving model. The magnitude and depth of the vertical wind shear, the strength of the diabatically generated cold pool associated with the convective storm, and the structure of the sea breeze-MABL boundary will be altered in the suite of idealized numerical sensitivity tests. Some of the scientific questions that motivate the study include: Is the low- or mid-level shear more influential on the evolution of the QLCS? What is the source region of the air being ingested into the QLCS? How do the QLCS characteristics change as the system interacts with the MABL boundary and as it moves offshore?