AP Blue Sky Science: How does thunder form? Jul 10, 2019 Updated Jul 10, 2019 Facebook Twitter SMS Email Print Save When lightning occurs, a large discharge of electricity causes the surrounding air to vibrate as it passes through the atmosphere to the surface. Tags Wire Field59 Blue-sky-science More video Blue Sky Science: How do hot air balloons work? Here's a quick guide to navigating Amazon Prime Day 2019 'Sweetbitter' Sneak Peek: Should Tess Trust Simone? Facebook Twitter SMS Email Print Save Most Popular State police: Auburn man charged with raping girl Wells College placed on probation by accrediting organization Authorities search for rapist who removed monitor bracelet in Skaneateles Port Byron man caught by the FBI soliciting a minor pleads guilty Three Cayuga County-area schools acknowledged by state View All Promotions promotion spotlight What should you get Dad for Father's Day? AP promotion spotlight How much coffee trivia do you know?