Officials in Lethbridge County, southeast of Calgary, have ordered an evacuation for people living in an area just west of Lethbridge due to a raging grassfire that started on Sunday afternoon.

County Reeve Lorne Hickey said the wind was gusting up to 100 kilometres per hour in the area, and RCMP were going door-to-door telling people they had to flee.

Hickey said the wind was blowing toward the city of Lethbridge, and some neighbourhoods there were on an evacuation alert.

"We're trying to get a handle now on where it's moving and how fast it's moving," Hickey said.

Firefighters in Lethbridge were also dealing with a blaze in an industrial building where the structure's roof had blown off.

In Calgary, where the storm roared through earlier in the day, traffic in the downtown core was shut down and officials warned residents to stay indoors.

"Right now, there's just so much stuff falling off buildings that we're struggling to keep up with calls," said Det. Dean Vegso of the Calgary Police.

Despite the strength of the storm and the extent of the damage, police in Calgary said no injuries have been reported.

Environment Canada says gusts of over 100 kilometres per hour were reported in some parts of southern Alberta on Sunday afternoon.

In High River, south of Calgary, residents were told to leave an apartment building after municipal officials said a fire wall had separated from the building.

The province's emergency alert system has broadcast a warning on radio stations that residents should stay away from windows, and should watch out for flying debris.

"It's a lot more severe out in the country where there isn't anything to block the winds when it's coming across the fields," said Jillian Millar, who drove south from Calgary on Sunday afternoon with her husband to pick up their daughter from a party.

"We didn't realize it was as bad as it was when we left the house," she added.

Millar said farm animals were seeking shelter behind whatever they could find. She said she saw horses huddled beside a parked school bus.

The City of Calgary said several large windows were ripped out of the TD Square office building, and one firefighter working downtown said bits of debris from one building were breaking off and shattering glass on a neighbouring building.

The firefighter said it was "raining glass" in the area.

Police said there were parked cars that had been crushed by trees, but fortunately no one was inside.

Locksmiths were needed to get at some highrise balconies where the residents weren't home, but firefighters feared their barbecues may have been damaged and were leaking gas.

Several crossing arms along Calgary's light rail system were also broken off by the strong wind and power was knocked out briefly to a number of homes.

RCMP are advising that large vehicles should stay off Highway 2 south of Calgary between Nanton and Fort Macleod. Police have also warned that drivers of large vehicles on the Trans-Canada Highway in southeast Alberta should slow down because of the wind.

There were no reports of injuries.

"That's incredible, really,when you think about it, because we've had vehicles crushed by trees," said Duty Inspector Paul Stacey.

Despite police closing traffic to Calgary's downtown, the owner of a Calgary sports bar in the city's core said he still made it to work, and he said football fans were still getting in to watch the Grey Cup on his television screens.

Charlie Mendelman said he saw the police roadblocks on his way into downtown, but was able to find a way around them.

"I was born and raised in Calgary, so I know the streets really well," Mendelman said.

Police said it was fortunate the windstorm hit on a Sunday.

"There would be a lot more people walking if it was a weekday," Vegso said.