A-Train-Based Analysis of Frontal Cloud and Precipitation Structures: A Case Study

Extratropical cyclones are an important factor in regulating Earth's energy balance and providing a considerable amount of precipitation in the temperate climate zones. A preponderant amount of moisture present in an extratropical cyclone is transported through the warm conveyor belt, an airstream of ascending moisture that rises from the boundary layer to the upper troposphere. Previous research has shown that when the warm conveyor belt strengthens, there is a positive correlation with rain rate within the cyclone as it experiences nearly 100% efficiency at precipitating all poleward transported moisture. Given the large impact that extratropical cyclones and their warm conveyor belts have on the general atmospheric circulation, it is important to conduct research to better understand the relationships between water vapor content, storm dynamics, frontal processes and the associated precipitation distribution.

The week of Thanksgiving Day in 2006, an extratropical cyclone formed off the coast of Florida and slowly travelled along the eastern seaboard for approximately five days. Copious warm conveyor belt transport of water vapor resulted in coastal flooding in the Carolinas and over an inch of snow in portions of Georgia and South Carolina. Multiple overpasses of this long lived and nearly stationary cyclone were obtained from NASA's Earth Observing System Afternoon-Train (A-Train) Satellite constellation. When combined with winds from an operational numerical analysis, this project was able to use data from the A-Train to observe and understand the evolution of the warm conveyor belt cloud and precipitation structure. Our results demonstrate the value of an analysis that combines satellite and numerical model data, providing insight into the relationships between mesoscale cloud and precipitation features and cyclone scale dynamics and thermodynamic environment.