Tuesday, 14 May 2002: 2:45 PM
Analysis of Lightning Cloud-to-Ground Flash Activity for National Aviation choke point region Studies
This paper reports on a preliminary study on the major aviation National Choke Point region of the United States (US). The basis of the study is an examination of Hovm÷ller-diagrams of lightning cloud-to-ground flash density variations, covering the National Choke Point region defined as the area of the US that extends east from approximately Chicago to Boston, MA in longitude (60-100░ W) and north from central Georgia to northern Michigan in latitude (34-46░N). This region experiences the highest volume of air traffic within the US and is often subject to significant air traffic delays due to inclement weather. Data from the National Lightning Detection Network (NLDN) are used to generate plots of lightning flash rates on distance versus time plots (Hovm÷ller diagrams). These plots are similar to those used in a previous study that compared lightning data with rainfall measurements derived from NEXRAD radar data. The lightning Hovm÷ller plots have a spatial resolution of 0.05░ in latitude and longitude and a temporal resolution of 15 minutes. The results are consistent with typical US weather patterns and clearly illustrate the seasonal and diurnal pattern of thunderstorms. The diagrams clearly show the behavior of thunderstorms in this region, including their motions, extent and intensity. These and other features of thunderstorms evident in the diagrams are examined in terms of their tactical and strategic importance to aviation operations.