Evaluation of the Multi-Radar/Multi-Sensor System for Refining Requirements

The Analysis and Nowcast Branch (AFS11) within the Analyze, Forecast, and Support (AFS) Office of the National Weather Service (NWS) is responsible for developing operational requirements for analysis and forecasting systems used by NWS forecasters. AFS11 surveys the forecasting field and develops requirements for various modeling, data processing systems and decision-making tools.

A proven decision-making tool used by forecasters is the Multi-Radar/Multi-Sensor System (MRMS). MRMS is a system with fully-automated algorithms that quickly and intelligently integrates data streams from multiple radars, surface and upper air observations, lightning detection systems, satellite observations, and forecast models. MRMS products are readily available to public and private entities via multiple data feeds and visual platforms.

With a set of refined draft requirements for MRMS improvements based on over 200 survey field responses, a project team was created to collect and evaluate corroborating cases to improve MRMS where it struggled. This study reports on our efforts to confirm and/or revise the draft requirements by focusing on the reduction of ProbSevere product biases, and improving precipitation estimation and FLASH parameters. In addition, this study centers on more observational datasets inclusive of model forecasts, all while reducing operational latency. We found 21 representative cases that reveal systematic or common biases as well as output inadequacies that yield forecast challenges. Our report summarizing case analysis and findings concludes with a series of recommendations that validate the final requirements.