The Global Energy and Water Cycle Experiment (GEWEX) Continental-scale International Project (GCIP) Enhanced Seasonal Observing Period - 1996 (ESOP-96) takes place in the Arkansas-Red River basins as a data collection effort in a Large-Scale Area (LSA) of the entire Mississippi River basin. The Arkansas and Red River basins provide a number of watershed areas that are potentionally useful for hydrologic focussed studies. The ESOP-96 Data Set constitutes the fifth in a series of GCIP Initial Data Sets (GIDS-5).