TORONTO – Storms are wreaking havoc for travellers and airlines today, not only in Ontario but also south of the border as well.

More than 100 flights scheduled to depart from or arrive at Toronto’s Pearson International Airport today have already been cancelled due to a wicked winter storm, reports CBC News. Air Canada issued nearly three-dozen travel alerts on its website this morning for cities in Ontario, Quebec, parts of the East Coast and large parts of the U.S. northeast.

The airline is telling passengers to expect possible delays or cancellations due to freezing rain in cities like Toronto, Montreal, New York, Boston, Chicago, Philadelphia, Washington, Fredericton and Saint John.

To accommodate travellers, Air Canada is allowing those on affected flights to rebook without penalty (space permitting).

Similarly, Porter Airlines will also waive change fees if a flight is cancelled or delayed and a booking must be modified. Although all Porter flights were listed as on time early this morning, the company’s website said that “unfavourable weather may result in flight cancellations or delays.”

Environment Canada says the storm will bring heavy snow to some areas, while other areas will see rain, ice pellets and the possibility of freezing rain today and tomorrow.

Storms of a different nature are leaving paths of destruction in the Gulf Coast states in the U.S. A deadly storm system that spawned tornadoes on Tuesday killed at least three people in Louisiana and Mississippi and is expected to bring severe weather to the Carolinas this afternoon.

Meteorologists at the national Storm Prediction Center warned of the potential for more tornadoes, including some possibly strong twisters along parts of the Atlantic coast, including the Carolinas and Virginia.

In Alabama and Georgia, forecasters issued flash flood watches ahead of the storm system, which was expected to drop 1-2 inches of rain. The warnings were expected to be in effect through Wednesday afternoon. The northern part of Georgia was also under a wind advisory.

Today’s forecast for the Carolinas calls for possible flash flooding and severe thunderstorms, including damaging winds, hail and isolated tornadoes.

A possible tornado ripped through Pensacola, Florida on Tuesday evening, destroying an apartment complex and downing trees and power lines. No major injuries were reported. In New Orleans, a reported tornado caused some damage but no injuries near the main airport, while high winds ripped off roofs and downed trees around the greater New Orleans area.