Operational Challenges for Numerical Weather Prediction Models in Mountainous Terrain

Fleet Numerical Meteorology and Oceanography Center (FNMOC), under the direction of the Commander, Naval Meteorology and Oceanography Command, has the mission to operate global and limited area meteorological and oceanographic numerical weather prediction (NWP) models in support of the US DoD in operations, exercises, humanitarian assistance and disaster relief. FNMOC provides an around-the-clock operational watch floor and scientists who can configure limited area models within hours for any location in the world. High resolution models in areas with mountainous terrain test the limits of this rapid response capability. Steep slopes can create strong downslope winds that violate the Courant–Friedrichs–Lewy condition. Bitter cold temperature can play havoc with the land surface model or radiation schemes. Operational meteorological measurements are few and far between, so validation requires the use of non-standard data and techniques. We'll give examples of some recent projects and what we did to overcome challenges.