07 Jun 15 09:44, you wrote to Daryl Stout:   
      
    DS>>   I always apply the 30-30 rule:   
      
    HG> I have a 3 second rule. If the thunder comes at 3 seconds after the   
    HG> lightning it did hit something 1 km away and it's too late to grab any   
    HG> cables to disconnect them.   
      
   here we use a 4 second rule...   
      
   1. see lightening flash   
   2. start counting - 1onethousand, 2onethousand, 3onethousand, etc   
   3. stop counting when the thunder is heard   
   4. divide the count by four and that's how many miles away the strike was   
      
   dunno how favorably that compares with sound and 3 seconds per kilometer...   
      
   what's really wild is seeing lightening flashes and counting and counting and   
   counting and never hearing the thunder because it is so far away ;)   
      
   )\/(ark   
      
   ... Don't Switch Horsemen Mid-Apocalypse.   
   ---   
    * Origin:  (1:3634/12.73)