Using Ensemble Models for Probabilistic Turbulence Forecasting at the Aviation Weather Center/Aviation Weather Testbed

The Aviation Weather Center (AWC) is tasked with the production of GAIRMETs to identify enroute hazards such as turbulence, icing, and ceiling and visibility, in order to fulfill NOAA's mission of maximizing air safety and efficiency. While many independent turbulence diagnostics exist (i.e. EllrodKnapp, EllrodKnox, TKE, etc...), the emphasis in recent years has been to create a multidiagnostic approach (i.e. GTG). Instead of emphasizing a deterministic or categorical forecast, a multidiagnostic, probabilistic forecast has been constructed using the Short Range Ensemble Forecast (SREF) model. The end product is based on the probability of member agreement from the individual SREF members. Diagnostic weights and calculations vary based on the vertical level and extends from near the surface to the stratosphere. This algorithm has been input into the Aviation Weather Testbed Ensemble PostProcessor for experimental use, evaluation, and training from operational forecasters at the AWC. Initial verification, both subjectively from forecaster use, and objectively show promise.