The lightning density in Austria varies between less than 1 and more than 5 flashes per km2 and year. The figure below shows the 10-year (2003 – 2012) mean annual ground flash density, using a 5 km x 5 km grid size. Most of the sites in Austria with flash densities exceeding 5 CG-Flashes per km2 and year are in the mountainous area of Styria and Carinthia.