Risk of thunderstorms Sunday, thousands remain without power

Sunday, March 27, 2016, 8:08 AM - Heavy rain and damaging winds loom for southern Ontario as Thursday’s ice storm effects linger with over 17,000 customers still without power.

Temperatures are expected to approach the mid-teens in southwestern portions of the province Sunday which will help melt the icy trees. However, thunderstorms are forecast to push into the region by late day, bringing heavy rain, strong winds and the possibility for small hail. Areas west of London could see the worst of these conditions.

“Of concern are the winds in behind the system overnight into Monday with wind gusts of 60-80 km/h. This could cause more damage to trees weakened by the ice storm,” said The Weather Network meteorologist Matt Grinter.

Total rainfall amounts of 25-50 mm are expected with this system. The wet conditions look to taper off by Monday afternoon. Rainfall warnings remain in effect for a large swath of southern Ontario, including Toronto and extending into parts of southern Quebec.

“Rainfall warnings are issued when 25 mm or more of rain are expected within 24 hours, when the ground is frozen or saturated and has a reduced ability to absorb this rainfall,” Environment Canada reported Sunday morning. “Heavy downpours can cause flash floods and water pooling on roads. If visibility is reduced while driving, turn on your lights and maintain a safe following distance.”

ICE STORM SUMMARY

As much as 30 mm of ice accretion covered tree branches and power lines in the worst-hit area. Though ice accretion in most other places and southwestern Ontario were more in the 5-15 mm range, the extra weight was bad news for hydro customers as the winds picked up Friday morning.

RELATED: The ice storm in pictures

Downed tree branches and power lines were widespread over much of the region. On Thursday night, in the midst of the ice storm, there were reports of bright flashes as substations sparked.

The clean up continues across the region, especially for communities like Fergus and Orangeville that were hit with the same severity of the 2013 storm.

The number of outages reported by Hydro One hovered around the 100,000 mark for much of Friday morning before declining in the afternoon, but by Sunday afternoon, around 22,000 Hydro One customers were still in the dark. The high number of outages is due to the stiff winds knocking tree branches onto power lines.

Thursday was an ordeal for drivers across the region, with hundreds of collisions and calls for assistance reported in the GTA alone. At least one fatality was reported after a head-on collision between one vehicle and a transport truck.

In the skies, the conditions caused the delay or cancellation of 38 per cent of flights at Pearson Airport, 61 per cent at Toronto City Centre and 34 per cent at Macdonald-Cartier in Ottawa on Thursday.

Look below for more details on outages and transportation.

Outages

• All power utilities
• Enwin (Windsor)
• Enersource (Mississauga)
• Burlington hydro
• Guelph Hydro
• Hydro One
• Hydro Ottawa
• Utilities Kingston
• KW Hydro
• London Hydro
• Milton Hydro
• Niagara Power
• North Bay Hydro
• Oakville Hydro
• PowerStream
• Sudbury
• Thunder Bay Hydro
• Toronto Hydro
• Waterloo North Hydro

THE NEXT ONE

An upper level trough looks to intensify across the Midwest and into the Great Lakes basin late Wednesday into Thursday. Cool air from the north will help charge this system which is expected to bring thunderstorms and powerful southwesterly winds gusting up to 100 km/h in parts.

Check back for updates on this system.

POLAR VORTEX

Looking ahead into the long range, a cold blast is expected to hit Ontario, bringing the risk of lake effect snow and well below seasonal temperatures for early next week.

SOURCES: The Weather Network | CBC News | FlightAware