Incredible time-lapse footage of a dirty thunderstorm taken during an eruption on one of Mount Etna's craters. <br /><br />The video, filmed this week on the Voragine Crater on Mt Etna in Sicily, shows the awe-inspiring weather phenomenon, which involves lightning forming inside a volcanic plume. <br /><br />Etna, Europe's tallest active volcano, erupted on Thursday spewing out ash and lava.
