Sherri Powers of Austin wants to know how lighting forms and when is it safe to go outside again.
Lightning is a giant spark caused by natural static electricity. As the clouds grow into storms, all the hailstones colliding with each other cause a negative electrical charge to build up at the base of the cloud.
At the same time, positive charges form around objects near the ground. When the negative charges move near the ground it attracts the positive charges that are going upward.
In this case opposites do attract, when the charges race toward each other they connect and a powerful electric current is born.
The main factor for starting the electric generator is ice formation in the storm. The updrafts within the storm will keep the ice from falling and will let the ice build in the cloud. More ice colliding means more potential for lightning.
The most dangerous type is the bolt from the blue. This is when the bolt comes out of the back side of the storm and can strike 25 miles away where the sky is clear. Statistics show that 60% of victims are struck under blue skies after the storms have passed. This is why it is a good idea to wait 30 minutes or more after the rain ends.
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