The Rare Atmospheric Undular Bore Event Observed over Lake Ontario During the Morning of April 3, 2015

A rare atmospheric undular bore event occurred over Lake Ontario during the morning of April 3, 2015 and caused gravity wave clouds near the leading edge of the bore which were visible for several hours over the ice and open water of Lake Ontario. These atmospheric bore events occur when a density current intrudes into a less dense but stable layer of air capped by an inversion and forces the stable layer to lift. In specific conditions, the stable layer lifts smoothly and non-turbulently, with undular waves forming at the top of the stable layer that are often visible on GOES satellite imagery. Meteorological conditions associated with this event are presented, along with some background details related to atmospheric undular bore events.