The bitter cold temperatures continue to grip much of southern Ontario, including Toronto and the GTA.

Toronto remained under an extreme cold weather alert on Tuesday for the 17th time this winter.

On Monday, Environment Canada issued a windchill warning for parts of southern, central and eastern Ontario, including Toronto, the GTA, Hamilton and Barrie, warning of strong winds and falling temperatures producing windchill values of -30s.

Wind gusts of 50 km/h are expected on Tuesday, according to 680News meteorologist Harold Hosein, with a sun-cloud mix and scattered flurries for the afternoon. The forecast calls for a high of -14 C, but it will feel near -30 C.

Windy conditions will continue Tuesday night with gusts of 40 km/h, combined with cloudy periods and scattered flurries after midnight. The low is -21 C with a windchill near -30 C.

There are 44 cancelled flights at Pearson International Airport and passengers can expect delays due to de-icing.

Click here for the weather forecast. There are some school bus cancellations outside of the GTA. Click here for a list.

Meanwhile, the U.S. National Weather Service has issued winter storm alerts stretching from central Texas, through the Gulf Coast into Georgia, the Carolinas and southeast Virginia.

Schools are closed from Texas to Florida with forecasters warning that more than 15 centimetres of snow is possible in some areas that rarely see it. Other areas, such as New Orleans, are bracing for freezing rain.

Delta Air Lines officials say more than 1,800 flights have been cancelled.