An analysis of the synoptic and mesoscale forcing of the 08/09 March 1992 STORMFEST mesoscale convective system

摘要

A severe mesoscale convective system (MCS) developed in northeast Texas and southern Oklahoma during STORMFEST in 1992. The MCS, associated with a bulging dryline, produced five tornadoes, widespread flash flooding, large hail and damaging winds. An analysis of the root causes of this convective system was conducted using the coarse gridded Global Data Assimilation (GDAS) Final Analysis fields. This analysis is conducted to determine if the atmospheric processes that produce such severe convection are resolveable in coarse gridded data. Bulging dryline convection is associated with upper level jet streaks which are synoptic scale features. This research focusses on the interaction of the jet streak aloft, the dryline and an advancing cold front. Vertical motion associated with upper tropospheric ageostrophic wind accelerations and motion along a cold frontal surface act together in producing severe convection along a bulging dryline. These forces are resolveable in the GDAS fields.