Toronto residents braced for a weekend of snow after a storm from Alabama began to blow into the city on Friday with the forecast calling for snow in two stages on Friday and Saturday.

The snow caused some delays at Toronto's Pearson International Airport on Friday afternoon as thousands of travellers prepared to leave the city for March Break.

Trish Kale, spokeswoman for the Greater Toronto Airports Authority, said the airport is ready for the wintry weather. She said crews have begun to clear runways of snow.

"Unfortunately, we have seen a lot of snow this year. Preparing for this storm is normal for us in terms of how we deal with it," she said.

"About 24 hours ahead of time, we start to get our crews scheduled and on site. Now that the snow is falling, we will be out there clearing the runways and taxiways of snow. It's not an unusual event for us."

Krale said travellers should follow what has become standard advice for storms this winter: call ahead or check their airline's website for delays and cancellations before leaving for the airport.

"It's going to be a busy day," she said.

Environment Canada said Friday the storm would bring heavy snow to parts of southern and eastern Ontario.

Toronto, under a winter storm watch, was forecast to receive more than 20 centimetres of snow on Friday and Saturday.

Two centimetres were expected in the city on Friday afternoon, five cm on Friday night and 15 cm on Saturday.

Karen Matthews, a meteorologist with the CBC Weather Centre, said Toronto is on its way to a record snowfall this winter.

The city, according to snowfall amounts measured at Pearson International Airport, has had 178 cm so far this winter, while the record at Pearson was 207 cm, set in the winter of 1938-39.

"We're creeping up," Matthews said Friday.

The snow, which began Friday afternoon in southwestern Ontario, was expected to move into eastern regions by evening.

After a short break overnight, the second snowfall was expected to begin Saturday afternoon in southwestern Ontario and later over eastern Ontario. It isn't expected to ease for several hours.

"Keep in mind that the snowfall duration will be about 36 hours, but the heaviest snow will be Saturday afternoon into the evening," Environment Canada said.

The Niagara region and the Kingston and Cornwall areas could be hit hard, receiving up to 50 cm.

The Greater Toronto Airports Authority said more than 100,000 travellers are expected to pass through Pearson International Airport on Friday. It said it expects Friday to be the busiest travel day of March Break.