Today and every Saturday Earth Science Picture of the Day invites you to rediscover favorites from the past. Saturday posts feature an EPOD that was chosen by viewers like you in our monthly Viewers' Choice polls. Join us as we look back at these intriguing and captivating images.

Photographer: Leonardo Orazi 
Summary Authors: Leonardo Orazi; Jim Foster

The photo above showing a distant thunderhead looming over a range of the snow capped Alps was taken near Aosta, Italy, on May 11, 2013. It’s illuminated from within by cloud-to-cloud lightning, a tongue of which appears to flick the side of the 8,500 ft (2,591 m) mountain. During spring and summer, quickly developing mountain thunderstorms are a major concern for climbers and hikers.

Spring snow melt in the Alps, as well as in many mountain ranges in the Northern Hemisphere, has been occurring earlier in the season in recent decades than a century ago, however, the onset of the snow accumulation period in autumn has been little changed.

• Aosta, Italy Coordinates: 45.738855, 7.366692
• Related Links
  • Calgary, Alberta Lightning Display
  • Teide Volcano, Snow, Lightning and Orion
  • Cloud to Cloud Lightning on Jupiter
  • Leonardo’s Website
• Student Links
  • Severe Weather 101: Lightning Types
  • Lightning!
• Earth Observatory
  • Cloud Formations and Sunglint, Italy
  • Snow Cover

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