Satellite and ground based observations of lightning flashes in the stratiform and anvil regions of convective systems

Flashes in the anvil and stratiform regions of storms are identified and their statistics are analyzed from Tropical Rainfall Measuring Mission (TRMM) observations between 1998 and 2009. In total, ~5% of all lightning flashes are observed in either the anvil or stratiform region. Global distributions and seasonal and diurnal variations of these flashes are discussed. Electric Charging Regions (ECRs) are identified by grouping areas with 30 dBZ radar echo at 6 km from TRMM Precipitation Radar (PR) observations. Then, flashes in the anvil and stratiform regions are associated to their nearest ECRs. About ~15% of all ECRs near lightning have been found to be associated with at least one stratiform or anvil lightning flash. The relationships between these flashes and their nearest ECRs are discussed. To validate the results from TRMM observations, ground-based observations from the Tropical Warm Pool International Cloud Experiment (TWP-ICE) are analyzed. Based on the results of both data sets, flashes in the anvil region are found to often occur near the edges of convective cells within single cell systems, and many of them occur in relatively early stages of convection. Stratiform flashes, on the other hand, are more common as convective systems weaken, and many of them occur within multicellular systems.