Today marks the 25th anniversary of a deadly tornado that swept through Edmonton, a day that's come to be known as Black Friday.27 people were killed in the storm, and more than 300 injured.    It was on July 31st, 1987 that a storm system spawned a massive twister that rolled across the city's east side, causing hundreds of millions of dollars in damage.
    Several people were killed in an industrial area, but most of those who died were in the Evergreen mobile home park in the city's northeast.