Australian Weather Calendar - November 2014

November photgraph by Marie Freitag

Storm spotter gets up close and perilous

Lightning occurs when the negative electrical charge in the lower part of a cloud and the positive charge in the upper part of the cloud become so great that they can overcome the natural resistance of the air, triggering a discharge. Thunder is the sound produced by the explosive expansion of air heated by the lightning stroke.

Thunder alerted Marie Freitag of Perth to a storm early on 4 January 2012. Marie has been chasing storms for five or six years and is a volunteer storm spotter for the Bureau. Between Beechboro and Caversham, she photographed the storm. ‘The lightning was pretty much every couple of seconds. It just cracked down.’

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