  A favorable environment for downbursts associated with deep convective storm
systems that occur over the central and eastern continental United States
includes strong static instability with large amounts of convective available
potential energy and the presence of a mid-tropospheric layer of dry air.
However, previous research has identified that over the central United States,
especially in the Great Plains region, an environment between that favorable
for wet and dry microbursts may exist during the convective season, resulting
in the generation of hybrid type microbursts. Hybrid microbursts have been
found to originate from deep convective storms that generate heavy
precipitation, with sub-cloud evaporation of precipitation a significant factor
in downdraft acceleration. Accordingly, a new GOES sounder derived product, the
GOES Hybrid Microburst Index, is under development and is designed to assess
the potential for convective downbursts that develop in an intermediate
environment between a wet type, associated with heavy precipitation, and a dry
type associated with convection in which very little to no precipitation is
observed at the surface.
