On the Multiple Intensity Changes of Hurricane Earl (2010)

While major advances have been made in forecasting hurricane track, intensity forecasting has been a large focus of recent tropical cyclone research. Some hurricanes dissipate before becoming high intensity storms, and others develop into major hurricanes, often making landfall. Given the lack of available widespread high-resolution data, model simulations are a useful tool for investigating the inner core thermodynamics and dynamics of storms, and how these factors relate to intensity changes. Simulations using the Weather Research and Forecasting (WRF) ARW Model are employed to examine the intensity and structural changes, including the Secondary Eyewall Formation (SEF), of Hurricane Earl (2010), which underwent Rapid Intensification (RI) beginning on 29 August and ending on 31 August, attaining a peak wind of 59.1 m s^-1 and a minimum central pressure of 931 hPa. Nested domains, with a relatively high resolution of 1 km in the inner domain, allows for sound investigation of the inner core region, and model validation shows the control simulation portrays the actual conditions fairly well. In fact, the simulation was able to accurately reproduce the SEF, which begins near the time of the storm's peak intensity and later concludes with the collapse of the inner eyewall. Results from experimental simulations are used to examine the potential relationship between intensity changes, SEF, and vertical wind shear, as well as the influence of the warm core on the eyewall structure.