NEW YORK (CNN/Money) - U.S. retailers struggled to salvage some of their lost sales Tuesday after the worst snow storm in seven years shut down much of the East over the long holiday weekend.

"The blizzard was a serious setback for retailers, especially since the Presidents Day weekend is a major day for sales," said Kurt Barnard, president of Barnard's Retail Consulting Group. "Most of the malls and independent stores were shut in the Northeast. "

Retailers traditionally have marked Presidents Day as the final clearance weekend for the Christmas holiday inventory before they transition into spring merchandise.

"Many retailers spent million of dollars on advertising, and that has also come to a nought. The storm was also a disappointment for consumers because they were also looking forward to it for weeks," Barnard said.

Some analysts suggested that most retailers probably will extend the special sales and discounts into the coming weekend.

J.C. Penney (JCP: up $0.57 to $19.29, Research, Estimates), which had closed about 270 stores in the Northeast, said it expected all but five to be reopened Tuesday. The company also said it will carry the special sales meant for last weekend over to the coming Friday and Saturday.

Wal-Mart (WMT: up $0.58 to $49.73, Research, Estimates), the world's biggest retailer, said the winter storm had forced the company to shutter all of its stores in the East and mid-Atlantic areas primarily because its employees could not get to work.

Wal-Mart spokesman Tom Williams would not say how many of the company's stores were closed but said not all would reopen Tuesday.

Williams added that worries about a terrorist attack prior to the storm helped to drive up sales of pantry items in the latest week as consumers stocked up on canned food, batteries and water. The company Tuesday posted fourth-quarter earnings that topped Wall Street estimates.

Anthony Chan, chief economist at Banc One Investment Advisors, said the impact of the blizzard also was likely to dent the February retail sales number, a worrisome thought after sales dipped 0.9 percent in January after growing 2 percent in December.

"[Retailers] won't make up the sales in two weeks," Chan said, "but over the next month they may make up at least half to three-quarters of the sales in the form of some discounting."

Meanwhile, Bill Angrick, CEO and chairman of Liquidations.com, an online auction service provider that helps retailers convert their excess inventory into cash throughout the year, said he expects the value of excess inventory that comes to it from merchants to rise to $200,000 a day, up about 33 percent from the same time a year ago, because of the lost sales on Presidents Day..