To assist partner NOAA/National Weather Service (NWS) offices in precipitation forecasting, the NASA Short-term Prediction and Research Transition (SPoRT) project transitioned the calibrated IMERG rain rate product for a preliminary evaluation during summer 2015. The IMERG rain rate is accumulated at 1-, 3-, 6-, 12-, and 24-hour intervals for dissemination to NWS forecast offices. Three regions were targeted for this evaluation, each with a participating NWS Weather Forecast Office and River Forecast Center: Alaska/North Pacific, Southwestern U.S., and Southeastern U.S./Puerto Rico. These three regions offer widely-varying characteristics, limitations, and requirements regarding the use of precipitation data in forecast operations. To evaluate the utility of the IMERG data, forecasters are providing feedback on how the IMERG product is used in operations, including documentation of the product's perceived strengths and weaknesses. In addition to this qualitative forecaster feedback, the “Early” and “Late” IMERG products are inter-compared quantitatively to current operational QPE products (i.e., Stage IV and Multi-Radar Multi-Sensor [MRMS]) using NCAR's Model Evaluation Tools (MET) in combination with a SPoRT-developed scripting package for the MET software. This presentation will summarize the qualitative forecaster feedback, as well as the quantitative comparison of the IMERG “Early” and “Late” product against the operational Stage IV and MRMS QPE products.