July 31, 1987 saw a devastating F4 tornado rip through Edmonton and parts of Strathcona County.
The Black Friday Tornado, as it's known in the region, packed winds peaking at 417 kilometres per hour, a borderline F5.
The second-deadliest tornado in Canadian history took 27 lives and injured 253 more. The storm roared through, cutting a 30 kilometre path that, at times, spanned a kilometre wide, touching down near Beaumont and tearing through Mill Woods, Refinery Row, Clareview and Evergreen Mobile Home Park. It was on the ground for over an hour.
In Fort Saskatchewan, Elly Wolff, who was 28 at the time, was leaving Fort Mall with her sister when a man came up to them, asking if they had heard about the tornado that touched down on the radio.
"That day, it was really quiet, there were not birds singing, there was nothing; it was just really dark and gloomy-looking," Wolff recalled.
The two sisters parted ways. Wolff went to her home in the Pioneer Apartments where she sat by her patio and watched.
"You could see the sky was getting greener and greener and the clouds were starting to rotate a little more than usual," she explained. "I thought to myself, oh my goodness, I don't know if it's going to hit here or what was going on."
Her sister phoned from her basement from underneath a mattress, asking her to come seek shelter in the basement. Wolff hesitated, unsure if she would make it.
"I was kind of hypnotised by looking outside because it was something that I'd never seen before but it was something that was [also] very scary."
Fort Saskatchewan was hit by the back end of the storm. It sent construction debris and barriers flying down the streets as heavy rain and large hail pounded the area.
For Wolff, the sights and sounds of July 31, 1987 are forever engraved in her mind.
"It was very scary for me, so every time I look at the sky, I always think of that day," said Wolff. "I watch the skies all the time."
At the time, there was no emergency alert system in place, merely a radio mention from Environment Canada. Because of Black Friday, the Emergency Public Warning System was put in place, later replaced by Alberta Emergency Alert. It also sparked the wide adoption of Doppler weather radar with the Carvel station, near Edmonton, being only one of three Doppler radar stations in use at the time of the twister. Fort Saskatchewan also installed emergency sirens, mounted high on poles around the city.
The tornado caused $332.27 million in damage. In 2016 dollars, that cost balloons to $623 million.