Evaluation of the Mountain Wave Forecast Model's Stratospheric Turbulence Simulations

Stratospheric turbulence (Stratoturb) is a well-known hazard to aircraft in flight. Forecasting mountain waves, specifically the breaking of these waves, is necessary to accurately predict the presence of Stratoturb. The Air Force Weather Agency (AFWA) requested a product with the capability of forecasting Stratoturb at 30, 50, and 70 mb using model data currently available. To facilitate their request, the Mountain Wave Forecast Model (MWFM) was acquired from the Naval Research Laboratory. MWFM turbulence forecasts generated twice daily over East Asia, using the AVN and MM5 models for initialization, were compared to 'S' layer turbulence analyses from the Rawinsonde Observation (RAOB) program, currently used operationally to warn aircrews. Actual verification of the MWFM forecasts was unachievable since in situ turbulence observations were not available, and as a result only subjective assessments of the MWFM's capabilities were possible. The MWFM was determined to be the superior forecast tool based on the temporal and spatial coverage provided when compared to RAOB as well as its promising ability to alleviate the reported overforecasting inherent to the RAOB analyses. Therefore, the MWFM, including code modifications made at AFIT, was recommended for use by AFWA. Further objective analysis of the model's accuracy should be conducted.