Marine Layer Stratus Study at Vandenberg AFB 16 August 2004 -17 September 2004

The intent of this study is to develop a better understanding of the behavior of marine layer stratus and fog at Vandenberg AFB, which accounts for 80-85% of aviation forecasting difficulties. Leippen's four phases of the marine Layer Fog/Stratus remains the best description of the marine layer stratus and fog developmental process at Vandenberg. The author's meteorological objective was to use Leippen's study as a starting point to evaluate synoptic scale through micro scale processes involved and identify specific meteorological parameters that were affecting the behavior of marine layer stratus and fog. After identifying those meteorological parameters, the study proceeds to evaluate how well the various weather models forecast them. The main conclusion derived from this study is that marine layer behavior is influenced by weak upper air dynamic features working in combination with boundary layer motions. This study highlights the importance of correctly forecasting the surface temperature by showing how it ties directly to the wind field. That wind field, modified by the local terrain, in turn establishes the low level convergence and divergence pattern and the resulting marine layer cloud thicknesses and visibilities. Three decision trees were developed from the study that should assist in developing a forecast for the marine layer (thickness, ceilings, and visibility), temperatures, and winds. Further research is encouraged to develop weight values to enhance the decision trees.