Recent and Future Improvements in Automated Icing Algorithms

Abstract

The goal of icing forecasting research being conducted at the National Center for Atmospheric Research (NCAR) for the Federal Aviation Administration’s (FAA) Aviation Weather Research Program (AWRP) is to provide timely and accurate forecasts of inflight icing conditions. The flying public wants to know not only where icing conditions are likely to reside, but also the probability of their occurrence and expected severity. Automated diagnosis and forecast icing products have been developed at NCAR and deployed at the Aviation Weather Center (AWC), where they provide this information to pilots, forecasters, and dispatchers. These products, known as the Current and Forecast Icing Products (CIP and FIP, respectively), have been approved for operational decision making by these groups. Recently, changes were made to both algorithms to accommodate the transition in numerical weather prediction (NWP) models, from the Rapid Update Cycle (RUC) to the Weather Research and Forecasting Rapid Refresh (WRF-RAP). This transition required some changes to the algorithms to handle updated model information and a verification of the results. The verification study confirmed that the new model had the desired effects on the icing products and also brought to light some interesting information on the handling of convection and supercooled large drops (SLD). During this transition other upgrades and changes were also made to the algorithms dealing with icing severity at night, the use of radar data, and the development of an algorithm testbed.