Evaluation of WRF performance for depicting orographically-induced gravity waves in the stratosphere

Orographically-induced gravity (buoyancy) waves can propagate through the tropopause to the stratosphere causing disruption to high altitude aircraft operations. High altitude turbulence (HAT) was first researched using U-2 aircraft in the mid-1960s and reported by Crooks (1965). He observed that HAT from mountain wave activity was more severe than turbulence associated with jet streams or convective activity. A few years later a severe downslope windstorm and turbulence event along the front range of the Rocky Mountains in Colorado was analyzed and reported by Lilly and Zipser (1972). Klemp and Lilly (1975) and Lilly (1978) concluded that this event on 11 January 1972 was precipitated by mountain wave activity occurring in the vicinity.