About 77 millimetres of rain fell on Ottawa in a matter of hours, according to Environment Canada. That's more than any other Aug. 10 on record, but surrounding regions saw even more, receiving between 80 and 110 millimetres. At the storm's peak, Hydro Ottawa reported 24,000 customers without power. Mycah Katz was practicing a drag performance in the basement lounge of his condo building when the power cut out.