Multi-sensor Precipitation Estimation for use by River Forecast Centers During Heavy Rainfall Events

The National Weather Service (NWS) has been using hourly radar-derived precipitation estimates from multiple radars to create regional precipitation mosaics for use by River Forecast Centers (RFCs). The radar estimates along with hourly rain gage observations and hourly satellite-derived are the main input into the RFC-wide Multi-sensor Precipitation Estimator (MPE). Here we describe the various components of the RFC-wide MPE which include: mean-field bias adjustment of individual radar estimates at multiple time scales, multi-radar mosaic, merging of radar and gage estimates, local bias adjustment, and use of satellite estimates in areas where radar coverage is poor and gage coverage is sparse.

MPE performance from three different regions of the United States including the Pacific Northwest, Western Gulf States, and the Middle-Atlantic will be discussed. We will also illustrate the MPE improvement over raw radar estimates during several recent heavy rainfall/flood producing events including Hurricane Floyd.