TiMREX/SoWMEX observations of non-synoptically-forced convection

The Southwest Monsoon Experiment/Terrain-influenced Monsoon Rainfall Experiment (SoWMEX/TiMREX) was conducted in southwestern Taiwan in Summer, 2008. The overarching goal was to better understand the Asian monsoon rainfall period to improve quantitative precipitation forecasting skill. Numerous heavy precipitation events associated with the Mei-Yu Front occurred during SoWMEX/TiMREX. Additionally numerous convection initiation events occurred in the absence of synoptic forcing. These non-synoptically-forced events may also contribute significant rainfall to the region.

The multitude of SoWMEX/TiMREX observations are combined to provide a project-long characterization of non-synoptically-forced thunderstorm formation events, as well as their evolution and their rainfall distribution. Non-synoptic forcing mechanisms include orography, sea breezes and outflow boundary initiation. The S-Pol radar reflectivity data are used to identify the location and timing of new convective development. The sounding and wind profiler data will be used to relate the longevity and propagation of the storms to the wind and stability profiles of the atmosphere. The surface station data and S-Pol radar refractivity field are used to determine if a relationship exists between low-level moisture and winds with storm initiation location and timing. The rainfall amounts from rain gauges and S-Pol rainfall accumulation algorithms will be compared to the storm initiation location, mean wind and stability profiles and storm advection characteristics. The objective of this study is to obtain a project-long characterization of non-synoptically-forced storms and their associated rainfall.