A Surrey mother is thankful her sons are unharmed after part of an elm tree crashed through the roof of their townhouse complex during a windstorm.

About half of a 15-metre-tall tree broke through the roof of the South Surrey home off 152 Street Tuesday shortly before midnight, shaking the house so much its residents thought there was an earthquake.

Elizabeth Hall said she was amazed but thankful that it didn't fall through her children's bedrooms or shatter their windows.

"I'm glad my kids are safe and everyone's OK," she said.

A large hole could be seen Wednesday where a portion of the roof had collapsed under the weight of the tree into a back room.

Hall said the tree sways every time there's a storm, but because of its size she never thought it would come down.

The sound was loud enough that it woke up the neighbours in the home next door.

"I literally jumped out of my seat. It's pretty scary," Natalie Kellner said.

Her four-year-old daughter was scared and cried, but also asked Kellner if the noise was Santa Claus.

An engineer ruled that the townhome is still structurally sound, though the roof will need repairs. Crews spent most of the day in the area assessing the damage and removing the tree.

The same storm that felled the giant elm in South Surrey knocked out power to thousands of residents of B.C.'s South Coast overnight and Wednesday morning.

Strong winds made landfall Tuesday evening ahead of a low pressure system coming in off the Pacific, bringing gusts as strong as 90 km/h in some areas.

The rain and wind plagued an area from Vancouver Island to the eastern part of Metro Vancouver, and brought a risk of flooding to lower lying areas.

The storm system left a big mess for hydro crews as trees and branches toppled into power lines. Outages were reported in Oak Bay, Burnaby, Delta, Richmond, Vancouver, Whistler and some of the southern Gulf Islands. The outage affecting the most people was in Langley and Surrey, with as many as 3,400 customers without power in the morning, but the other outages also affected hundreds or thousands.

More than 20,000 customers on the Lower Mainland and Sunshine Coast were without power Tuesday night. About 7,000 woke without electricity even with crews working through the night on repairs.

In Burnaby, lines were knocked down when part of a massive tree came crashing down on Parker Street, also damaging two homes.

Homeowner Darren Jankiprasad told CTV News he was thankful no one was injured.

"All of a sudden I heard this big rumbling noise, and all of a sudden a few seconds later I felt the entire house shake. I honestly thought it was an earthquake," he said.

The storm also left a group of people stranded on Grouse Mountain when the resort had to close its downhill area and lifts due to weather. The group included 70 kindergarten students from Surrey, and a 100-person film crew working on the hill.

"It's the movie industry and that's what happens in movies. You prepare for everything," said assistant director Damian Harper.

Those temporarily stuck at the top were given food and drinks at the chalet, and the kids were in the theatres watching movies with blankets and pillows provided by staff. Fortunately the mountain was able to reopen its lifts in the evening and everyone was able to leave.

"The kids had fun but the parents were scared," one of the parents told CTV.

Wind and rainfall warnings that were issued by Environment Canada Tuesday morning have been called off.

Snowfall warnings are in place elsewhere in the province, with as much as 25 centimentres expected to fall across Highway 3 – Paulson Summit to Kootenay Pass.

Similar warnings are in effect for: Peace River, Bulkley Valley and The Lakes, McGregor, Prince George and Williston.

With reports from CTV Vancouver's Nafeesa Karim, Penny Daflos and David Molko