The city says power outages are to blame for traffic light malfunctions at dozens of intersections Monday morning.
A city spokesperson told Global News the outages affected traffic lights at 38 intersections in the East Kildonan area and across the city.
Five other intersections experienced traffic light issues where the causes are being investigated by crews, according to the city.
The lights went out for thousands of Manitoba Hydro customers as thunderstorms rolled across southern Manitoba on Monday morning.
At about 8:15 a.m., a large swath of northern Winnipeg saw the power go out. At 8:20 a.m., Manitoba Hydro reported 5,050 customers were without power in the Kildonans and in St. James, and as the day rolled on, up to 20,000 customers were without power.
Manitoba Hydro said what exactly caused traffic lights to go out has not been determined.
A spokesperson for the power company there could be a number of factors behind a traffic light outage, including severe weather, vehicle collisions, animal contact and water from a downpour leaking into underground cable ducts causing cable faults.
Back in 2013, the city invested in upgrades to their traffic signal infrastructure which it said has reduced the number of specific moisture-related malfunctions of traffic signals citywide.
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