Aiken County Public Schools cancelled all afternoon and evening school activities today as a dangerous line of showers and thunderstorms, which has spawned tornados in Georgia and other parts of the country, is moving through the area.

A tornado watch has been issued for Aiken County until 1 a.m.

The storm is scheduled to move up until midnight, according to a special weather statement issued by the National Weather Service in Columbia.

Strong winds of up to 40 to 60 miles per hour are expected in some areas. Isolated tornados also are possible.

Meteorologists told NBC News that a number of factors have helped build the storm system's strength. They include unseasonably warm, wet air that southerly winds have pushed up from the Gulf of Mexico. That air is being met by cold air coming in from the Plains via Canada. Unusually high winds are driving that cold air eastward.

 The Weather Channel reported earlier today that two people had died in Georgia as a result of the severe weather.