Comparative Analysis on Structural Characteristics and Environmental Conditions of Two Kinds of Thunderstorm Gales

Abstract: There are significant differences on the morphology evolution and environmental conditions between two different types of thunderstorm gales, consecutively detected in the same area over Guangxi at nights from March 29 to March 31 2014. The gale in March 30, presenting with multiple isolated, loose and disordered single super-storms is a wet microburst, belongs to the low-level warm advection forcing category, besides that, the storm is triggered by a ground convergence line, and its stratification is conditional instability; While the gale in March 31, presenting with the squall line, formed by organized and closely spaced multi-cell storm, and at the rear side of which the inflow was clear, is a large range gales and belongs to the upper cold advection forcing category, furthermore, the storm is triggered by a southward cold front, and its stratification is convective instability. For the environmental conditions, stratification and dew curve of the thunderstorm gale in March 30 appears inverted V-shape, a relatively wet in the middle-level, dry in the low- level, and the temperature lapse rate nearly reaches dry adiabatic; While that of the gale in March 31 appears ‘funnel' shape, below 850hPa adequately wet, above significantly dry. In addiction, the vertical wind shear of gale in March 31 was larger, more conducive to the organized convection.