Lidar Observations and Comparison with Numerical Simulation of a Lake Michigan Land Breeze Front

As a part of the Lake-Induced Convection Experiments (Lake-ICE), on December 21, 1997 the University of Wisconsin Volume Imaging Lidar (UW-VIL) observed a visually stunning example of a shallow (~75-100 m) land breeze circulation over Lake Michigan. Backscatter returns revealed a steady offshore flow extending 1.5 to 4 km offshore, at which point it met the prevailing winds, which directly opposed the circulation. Since the prevailing onshore flow was weak enough to not overpower the local circulation, there was a consistent convergence zone offshore at the nose of the land breeze. Noting that the observed flow pattern is likely a simple combination of the large-scale atmospheric state and the local thermal forcing, we have simulated the day’s events using a high-resolution version of the University of Wisconsin Non-Hydrostatic Modeling System (UW-NMS). The lidar data was used as a validation tool for the model output.