Effect of tornadoes on electrical power lines has been discussed by Sébastien Langlois in his M.Eng. thesis : “Design of Overhead Transmission Lines subject to Localized High Intensity Wind”. McGill University, Montreal, QC, Canada, 2007 (available on-line on the “Theses Canada” portal). Work presents various national and international standards (ASCE, Cigré, IEC etc.), historical cases, as well as models for numerical simulation.