Storms soak Ottawa with 110 mm of rain on Canada Day, flooding roads and knocking out power

Flooding on Highway 417 near Pinecrest in Ottawa on Canada Day. Environment Canada says Ottawa has received over 100 mm of rain. (Camille Wilson/CTV News Ottawa)

Mother Nature disrupted Canada’s 159^th birthday party in Ottawa, as record rainfall and severe thunderstorms flooded roads, knocked out power across the region and forced the cancellation of Canada Day events.

Environment Canada says 110 mm of rain has been recorded at the Ottawa Airport as of 6:45 p.m., and storms continuing to move across the national capital region Wednesday evening.

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Environment Canada says more than 90 mm of rain had been recorded at the Ottawa Airport as of 5 p.m., with storms continuing to move across the national capital region Wednesday evening.

A severe thunderstorm warning has been lifted, but an orange warning – severe thunderstorm and a yellow watch - severe thunderstorm remain in effect. There is also a heat warning in effect.

“Environment Canada meteorologists are tracking a line of dangerous thunderstorms capable of producing damaging wind gusts, loonie to ping pong ball size hail and extremely heavy rain,” the weather agency said.

“A line of thunderstorms will move from west to east across the region and continue early this evening. 110 millimeters of rain has been reported at the Ottawa International Airport and may receive total amounts near 125 millimeters by this evening due to several thunderstorms.”

The previous rainfall record for July 1 in Ottawa was 58.9 mm, set in 1959.

Several Canada Day celebrations in Ottawa have been cancelled due to severe weather in the area, including the national evening show at LeBreton Flats and fireworks shows in Kanata, Barrhaven, Stittsville and Orléans.

In a statement on social media, Mayor Mark Sutcliffe acknowledged the heavy rain was causing localized flooding.

“Including flooded basements, damaged fencing, and isolated power outages across the city,” Sutcliffe said.

If your basement is flooding or water is entering your home, report it immediately by calling 3-1-1. This helps crews track impacts and respond faster. Avoid flooded streets and underpasses, and stay away from downed trees and power lines, which may still be live and dangerous.”

Sutcliffe said city crews and first responders are “actively responding to calls and prioritizing the most urgent safety risks.”

Hydro outages

As of 7 p.m., Hydro Ottawa was reporting approximately 28,000 customers without power across Ottawa, down from 35,000 customers at 5:40 p.m.

Outages were reported in Kanata, Stittsville, Centrepointe, Barrhaven, Beacon Hill-Cyrville and Orléans.

“Due to inclement weather and thunderstorms, we are experiencing multiple outages across our service territory,” Hydro Ottawa said.

“Crews have been deployed to assess damage and restore power where it is safe to do so.”

As of 7 p.m., Hydro One was reporting approximately 18,000 customers still without power across eastern Ontario, stretching from Gananoque and Brockville to Ottawa and the Ottawa Valley.

Flooding on roadways

The heavy rain caused temporary flooding of several roads across Ottawa, including large puddles covering Highway 417 in the Kanata and Nepean areas.

Large puddles covered the eastbound lanes of Highway 417 at Pinecrest and the on-ramp to the highway at 7 p.m., and large puddles could be seen on the highway in the Terry Fox Drive area. Flooding was also reported on Highway 416 between West Hunt Club Road and the Highway 417 split.

Ottawa police reported significant flooding on the following city streets:

• Corkstown Road ad Creekwood Crescent
• Greenbank Road and Banner Road
• Woodroffe Avenue and Knoxdale Road
• Moodie Drive at Highway 417 on-ramp
• Richmond Road and Holly Acres Road

Extreme heat warning

It’s day two of the orange heat warning in effect for Ottawa and eastern Ontario.

Environment Canada is calling for daytime highs of 30 to 35 between today and Saturday, with the humidex making it feel closer to 45.

“The hottest conditions are expected to continue into Thursday, with maximum temperatures up to 35 degrees Celsius expected,” the weather agency said.

“Minimum temperatures of 21 to 25 degrees Celsius will provide little relief from the heat. Hot and humid air can also bring deteriorating air quality and can result in the Air Quality Health Index approaching the high-risk category.”

The temperature hit 30.5 C today, with the humidex making it feel like 43.

The orange level on Environment Canada’s colour-coded scale refers to weather that is likely to cause significant damage, disruption or health impacts. Environment Canada is advising residents to take steps to protect themselves from the heat.

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Environment Canada recommends taking the following steps to deal with the heat:

• Limit exposure to the sun and heat
• Wear lightweight and light-coloured clothes
• Close blinds and shades, and open windows if it is cooler outside than inside
• Turn on air conditioning and use fans
• Move to cooler areas of your living space
• If there are no cool areas in your living space, move to a cool public place like a pool, cooling centre, community centre or library
• Drink water before you feel thirsty to replace fluids

The organization says air quality may be poor due to the heat and humidity, and the UV index is expected to reach 9 or higher.

Both the orange warning-heat and yellow watch-sever thunderstorm cover much of eastern Ontario and a full look at the warning zones can be found on Environment Canada’s website.

Forecast

Showers are expected to end this evening then partly cloudy with a 40 per cent chance of showers. Low 23 C.

Thursday will see a mix of sun and cloud with a 40 per cent chance of showers and the risk of a thunderstorm. High 35 C.

On Friday, expect 33 C and a chance of showers.

On Saturday, expect 31 C and a chance of showers.

On Sunday, temperatures are expected to dip below 30 C, reaching a high of only 29 C.

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