Identifying Sea and Bay Breeze Driven Convection and Common Locations for Initiation in Mobile County, Alabama

Sea and bay breeze driven thunderstorms are a common occurrence along the Gulf of Mexico Coast every summer. These summertime thunderstorms pose a problem to forecasters, due to the difficulty of predicting the exact location of development. These storms can cause flash flooding, strong winds, and plentiful lightning, that can cause serious damage to property and even life. However, in terms of agriculture, these thunderstorms can be beneficial to farmers who count on this almost daily rain for their crops. This research will identify the most common location where these storms initiate due to sea or bay breezes in Mobile County, Alabama. In this project, sea and bay breeze driven convection (i.e. thunderstorms) will be identified for the years 2009, 2010, 2011, and 2012 using radar data from the Mobile Doppler weather radar (KMOB WSR-88D). Three different triggering mechanisms will be analyzed in order to identify the reasons why the convection might form in a given location. These mechanisms include the sea and bay breeze interaction with elevation, the collision of sea and bay breezes, and the vertices in the the sea or bay breeze formed by the natural shape of the coastline. The locations of all three of these convective initiation types were mapped using ArcGIS to help identify the most common location for the development of these summertime thunderstorms. The results indicate that most sea breeze driven thunderstorm storms occur in the lower part of Mobile County. From radar imagery, it was observed that two vertices typically occur in the sea breeze front in Mobile County. Convection was observed to form in these vertices as well as in the southeastern part of the count where the sea and bay breeze collide. The ArcGIS maps show that the vertices and the interaction between the sea and bay breeze are the most common producers of sea breeze or bay breeze driven convection. The sea or bay breeze interaction with elevation, as show in the ArcGIS maps, is not as evident as the vertex mechanism. This is possibly because the majority of the storms formed in the lower 13-15 miles of the country, before higher elevations occur.