An Operational Technique Used to Detect “Mountain Wave Signatures”: A Forecast Methodology for Severe Westerly Winds in the Mountains of West Texas

Occurrences of extreme winds in the mountains of west Texas have historically posed significant forecast challenges for the region's operational meteorologists. Public impacts from such events have increased since the 1930s, when surface weather observations began at Pine Springs in the Guadalupe Mountains and with the construction of a world-class astronomical research facility in the Davis Mountains. Guadalupe Mountains National Park, including a portion of U.S. Highway 62/180 through Guadalupe Pass, is notorious for the hurricane force westerly winds that frequently occur there during the cool season. These events threaten the safety of park visitors, motorists and aircraft, and aggravate critical fire weather conditions. Synoptic patterns that favor severe mountain winds in the region have long been recognized, but pattern recognition-based forecasts and warnings have traditionally been short-fused and lack specificity with regard to timing and magnitude of anticipated wind events. Improved resolution and performance of operational weather prediction models during recent years has allowed forecasters to refine mountain wind forecasting methods, and improve upon the generalized predictions of the past. Prognostic model signatures that correspond to severe winds associated with vertically-propagating mountain waves have proven operationally useful in producing detailed and accurate forecasts and warnings for hazardous mountain winds. Incorporating a “mountain wave signature” (MWS) methodology, utilizing North American Mesoscale (NAM) model cross-sections of vertical motion and potential temperature, has allowed for longer range forecasts and warnings that accurately predict the onset of severe mountain winds, their magnitude and duration.