A New Convective Index for Africa

Severe wind gusts and thunderstorms have been difficult to forecast in Africa. Traditional convective forecast tools (e.g. T1, T2, and Snyder Indices) do not accurately portray potential for thunderstorms in Africa. A new gust and precipitation tool could be produced for increased forecast accuracy of these convective events. In order to increase forecast accuracy for thunderstorms in Africa, this research effort will use the Galvez-Davison Index (GDI), a convective index for a region with a similar latitude as the region used in this research, to investigate a new convective parameter that is tailored for our region of study. The GDI was specifically created for tropical regions, the Caribbean, and utilizes temperature, moisture, mid-level stability, dry air entrainment and an optional elevation factor to calculate convective potential. These characteristics along with the emphasis on mid-level stability make the GDI especially good for forecasting thunderstorms in the tropics. In this research, the GDI will be calculated using NCEP FNL Operational Model Global Tropospheric Analysis, but also modified for several locations in Africa to account for the dry air over North Africa and mid-level stability. This modified GDI will be evaluated to determine how well the new index forecasts potential for convection in Africa. It is hypothesized that a new index tailored for Africa will improve thunderstorm forecasting for the region, furthering research on the meteorological conditions that are conducive to convection, high wind gusts and precipitation in Africa.