Nova Scotia flood catastrophe — what went wrong?

Digital WritersThe Weather Network
Digital Writers

Tropical downpours unleashed significant flash flooding across the Halifax area last Friday, with a provincial state of emergency that remains in place. The Weather Network meteorologists Chris Scott and Tyler Hamilton explain how and why the Nova Scotia floods were so catastrophic.

An entire summer's worth of rain fell in just a couple of hours on Friday, July 21, as an unprecedented deluge swept over southern Nova Scotia.

MUST SEE: Nova Scotia’s historic rains would’ve smashed records in Florida

Parts of the Halifax Regional Municipality recorded more than 250 mm of rain during the prolific thunderstorms that persisted through the afternoon and evening hours.

The average summertime rainfall in Halifax is usually around 270 mm.


"This certainly ranks as one of the highest impact flash floods in Canadian history," says Chris Scott, Chief Meteorologist at The Weather Network.

A deeply tropical airmass flowing over the Maritimes was responsible for the historic rains that hit. Days of record warm temperatures and soupy humidity also helped to set the stage, as the enhanced moisture acted like a reservoir for the storms to tap into.

Friday's thunderstorms repeatedly developed and moved over the same areas like train cars on railroad tracks. This created a classic "training" storm setup that's responsible for some of the most intense flash flooding possible.

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"The storms just kept coming to the same place for about five to seven hours on Friday, and that's what did the damage," Scott says, adding that the intensity of the rainfall over such a short period of time resulted in similar storm totals to that of a hurricane.

Baron - NSRainfall - July25

"This situation relates to Hurricane Beth back in 1971 with similar types of rainfall amounts, however, that was over a longer period of it's all about the intensity. That's why this was not only a big event, but a historic one, which did things we've never seen before in this part of the country," says Scott.

WATCH: Body of missing man, human remains found after N.S. floods

On Monday, the body of a missing 52-year-old man was found, as well as unidentified human remains, in an extensive search for four missing people after two vehicles were submerged in the devastating floodwaters in West Hants.

Nova Scotia Premier Tim Houston expressed his condolences from the West Hants RCMP detachment in Windsor, Nova Scotia on Monday.

"It's a heartbreaking day for our province," he said. "We can rebuild roads and bridges and buildings but we can't bring people back, and the legacy from these floods will be the incredibly tragic loss of life."

SEE ALSO: Mandatory evacuation order issued for campground near Mahone Bay due to flooding

Now the question remains -- can we immediately tie this recent flood catastrophe to climate change? Be sure to watch the in-depth video above with Chief Meteorologist, Chris Scott and The Weather Network's Tyler Hamilton.

With files from Dennis Mersereau, The Weather Network