Washington, Feb 7 (DPA) More than 60 centimetres of heavy snow brought the US Mid-Atlantic region to a standstill, leaving thousands without power and forcing most traffic of the roads.

Wet snow had been falling since Friday morning, coating power lines that collapsed under the strain leaving some 100,000 homes without electricity in Maryland and Virginia.

As of 0230 IST Sunday, some 50 centimetres had fallen in the US capital, with more than 60 inches in suburban Washington, as flakes continued to fall, the National Weather Service said. Heavy winds of 32 to 48 km per hour, with higher gusts, made for low visibility across many of the seven states affected by the storm, it said.

The storm could be the worst in 90 years in the Washington region, local television forecasters said.

Washington's metro system's above-ground stations remained closed Saturday after shutting down late Friday, and bus service was also halted.

Few drivers were seen on major Washington thoroughfares, with only an occasional snowplow visible on traffic cameras. Hospitals put out calls for 4-wheel drive vehicles to transport doctors and nurses to work and retrieve ill patients.

Virginia declared a state of emergency even before the first flake fell around noon Friday. Universities and schools were closed, and government offices shut down several hours ahead of schedule to enable people to head home before the snowstorm hit.

Local pundits were calling the storm "snowmageddon" and "snowcopalypse." Grocery stores had empty shelves after residents prepared for a long weekend at home, stocking up bread, milk and toilet paper.

The storm system - a result of the El Nino weather affect, meteorologists said - has been heading up from the south all week, where it dropped rain and lesser amounts of snow.

Winter storm warnings were in place from southern Indiana eastwards to New York City and south to North Carolina. The blizzard warnings included Philadelphia, Delaware and the New Jersey coast, according to the National Weather Service.

Delta Airlines cancelled all flights to and from Washington, Baltimore and Philadelphia Saturday but said it hoped to revert to normal schedules Sunday.

Amtrak cancelled most of its train services from Washington headed south.

Washington Mayor Adrian Fenty declared a snow emergency, which went into effect Friday morning and prevents people from parking on certain streets so snowplows can get through.

The Washington region already received a massive snow storm in December when 40 centimetres fell, and this weekend's storm was a rare second major storm within one season. The record snowfall for the capital region was 70 centimetres in January 1922.