The National Weather Service (NWS) provides hydrometeorological forecasts as part of its commitment to the preservation of life and property. The ability to estimate real-time precipitation rates using remotely sensed data combined with "ground truth" precipitation gage observations is critical for the issuance of hydrometeorological river and stream forecasts and warnings. To meet this need, the Multi-sensor Precipitation Estimator (MPE) program, currently used only at NWS River Forecast Centers (RFCs) to measure precipitation, has been modified and enhanced to also be used at NWS Weather Forecast Offices (WFOs). This new application consists of a graphical user interface (GUI) which facilitates the manner in which the forecaster interacts with estimated precipitation amounts, manages meteorological and hydrological data, and monitors and quality controls observed data. The areal rainfall assessments generated in MPE are based upon both remote sensing techniques (radar) and actual observations (rain gages) and are used for display and river modeling purposes.

The NWS WFOs are tasked with the responsibility of estimating rainfall for the generation of timely and accurate forecasts of flash floods, and of headwater river and stream stages. This new version of MPE promises to markedly improve the ability of NWS WFOs to estimate precipitation amounts by allowing interactive review and incorporating a rainfall bias adjustment algorithm. These values may then be used as input to the Site Specific Hydrologic Prediction function to produce stream and river stage forecasts for headwater basins. In addition, the MPE bias factors computed by comparing radar estimated precipitation amounts to observed rain gage amounts will be passed into the Open Radar Product Generator (ORPG) for incorporation into WSR-88D precipitation products. This paper will discuss the operation and enhanced functionality of the new MPE program and how it will be an indispensable precipitation estimating tool at both NWS WFOs and RFCs.