A comparison of precipitation estimation techniques over Lake Okeechobee, Florida

Lake Okeechobee, located in southern Florida, is an important component in the regional hydrologic system. Currently, the Southeast River Forecast Center (SERFC) is setting up a forecasting scheme for Lake Okeechobee and its major inflows. An important aspect in calibrating the system is estimating the depth of direct precipitation over the water surface. Within this project, National Weather Service (NWS) and South Florida Water Management District (SFWMD) surface gauges, along with stage III multisensor precipitation estimates, are used to create time series of mean areal precipitation ( MAP). The computed MAP values are compared in order to find the relative differences between them, and to determine the utility of using each data source for calibration and in future operations. It was found that the SFWMD gauge-based MAP was the most useful data source, because it had a suitable period of record and the SFWMD gauges had a better spatial sampling of precipitation over the lake surface. The radar-based stage III estimates were not found to be a useful source of data, despite the superior spatial sampling resolution, because they had too short a period of record and a number of changes in the processing algorithms made the associated MAP nonhomogeneous and inappropriate for model calibration.