The diurnal cycle of warm season rainfall frequency over continents

There are both commonalities and quantitative differences associated with organized convective rainfall regimes among the continental regions examined so far. The most prominent commonality is associated with the elevated source for convective triggering and the subsequent dynamical organization upscale in the presence of moderate shear and adequate CAPE. What is most surprising is the statistical similarity of events in seemingly dissimilar environments (e.g. tropical easterly jet and deep westerly regimes). The full significance of this observation is not fully understood but likely central to more successful representations of convective rainfall in global climate system models. Some things that are evident in the results are: • Some deep tropospheric shear (∼10^-3) is essential to the upscale organization of convection and attendant rainfall that may be diurnally forced both locally and remotely. • Sea and land breezes play an important role in triggering convection that often constructively interacts with complex terrain and other sources of convection to produce diurnally modulated systems with both local and remote effects. By the time of the Conference we expect to provide comparable results fromboth Europe and the Amazon region.