FULGUCrest currents in a typical lightning stroke exceed 20,000 amps. Typical lightning current rate-of-rise times can exceed 8kA/microsecond, and lightning events often contain many discharge strokes each lasting from 30 to 40 microseconds. Lightning travels at approximately 60,000 miles per second, roughly one third the speed of light. Lightning temperatures have been recorded at five times the heat of the sun, or 50,000°F. The column of air around a lightning stroke is heated so violently that a sonic boom is created. In the end, up to 230,000 amps can be packed into a lightning stroke less than an inch in diameter. Anything electronic is subjected to the high electromagnetic voltage fields that lightning creates. Field meter readings in an average thunderstorm can exceed 15,000A/meter of cable.

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