The "Human Over the Loop (HOTL)" for Gridded Weather Hazard Products                 In–flight Icing, Turbulence, Ceiling and Visibility (C&V)

RAL began a five–year cooperative agreement with the National Weather Service in 2010–the Aviation Weather Cooperative Agreement (AWCA). A major part of the R&D vision for the AWCA is furthering the study of the "how" and "why" of HOTL forecasting for gridded weather products. The overarching goal of this work is to evaluate turbulence, in–flight icing, and C&V algorithms on the Interactive Correction in 4 Dimensions (IC4D) Workstation at the AAWU and the Aviation Weather Testbed. Objectives are to evaluate performance and benefit of HOTL manipulation of gridded numerical weather prediction models and aviation weather hazard algorithms. The National Center for Environmental Prediction's Model Development Laboratory has developed the IC4D Workstation for HOTL manipulation of gridded numerical weather prediction models and aviation weather hazard algorithms. This has been undergoing testing at the Alaska Aviation Weather Unit for the past two winters. The Forecast Icing Severity algorithm has been installed and AAWU forecasters have been examining the output on a daily basis. While the forecasters have been using the interactive workstation to alter the automated icing forecasts, perhaps the most valuable activity associated with IC4D testing, from the UCAR algorithm developers' standpoints, is the focused attention on performance of the algorithms in a new and somewhat unfamiliar environment. AAWU forecasters have documented case studies of icing events, demonstrating various levels of skill of the algorithms, and providing the UCAR researchers with valuable information. MDL recently installed IC4D at the Aviation Weather Testbed in addition to AAWU.