The GPM Ground Validation Composite Satellite Overpasses OLYMPEX dataset provides brightness temperature, precipitation, and total column water vapor estimates from multiple satellite overpasses including DMSP F16-19, GCOM-W1, GPM, MetOp, NOAA, and NPP for the OLYMPEX field campaign. The OLYMPEX field campaign took place between November, 2015, and January, 2016, with additional ground sampling continuing through February, on the Olympic Peninsula in the Pacific Northwest of the United States. This field campaign provides ground-based validation support of the findings resulting from the Global Precipitation Measurement (GPM) Core Observatory satellite. Data files are available from November 1, 2015 thru May 1, 2016 in HDF-5 format.