The Impact of Lightning in Intensity Forecasts of an Idealized Tropical Cyclone Using the HWRF Model

The National Oceanic and Atmospheric Administration (NOAA) created the Hurricane Forecast Improvement Project (HFIP) in 2010 with the ten-year goal of improving tropical cyclone intensity and track forecasts by 50% for days one through five. Part of this goal is to improve forecasts of the tropical cyclone rapid intensification. In order to contribute to this goal, we have investigated the role of lightning during the life cycle of an idealized tropical cyclone using the HWRF hurricane model. The hypothesis is that by being able to forecast the potential for lightning we will have a better understanding of the relationship between lightning and tropical cyclone intensification in terms of wind speeds and minimum pressure. This research is designed to address the following two questions: “Can we predict lightning in HWRF model with some degree of accuracy?”e.g. Space and Time; and “How well does the HWRF work with lighting parameterization model forecast lightning spatial distributions before, during, or after tropical cyclone intensification?” In order to address these questions, output from an Idealized HWRF tropical cyclone has been analyzed and compared to an Idealized HWRF tropical cyclone with lightning parameterization. A 120 hours simulation of two Idealized tropical cyclones e.g. Idealized tropical cyclone and Idealized tropical cyclone with lightning parameterization has been conducted to evaluate the evolution of the spatial distribution of lightning location and density. It is anticipated that the outcome from this research will further improve our understanding of tropical cyclone intensity fluctuation i.e. short term forecast related to lightning location and density. Results from this investigation will gave us a better knowledge of the mechanism behind lightning as a proxy for tropical cyclone steady state intensification and tropical cyclone rapid intensification forecast, consequently, move a step closer to achieving NOAA's goal of reducing the intensity error by 50% for days one through five.