The composite synoptic environment was examined for two active-MalphaCS (me
so-a-scale convective system) periods and two null-MalphaCS periods over th
e Yellow Sea region in 1993 to diagnose the large scale dynamical and therm
al conditions for the development of MalphaCS over the Yellow Sea region. T
he distinct contrasts were revealed in the composite diagnostic fields betw
een the active- and null-MalphaCS periods.