CHICAGO/NEW YORK (Reuters) - Retailers are struggling to meet even modest forecasts for the holiday shopping season this year after the “Super Saturday” before Christmas failed to live up to its nickname, industry research groups said.

The last Saturday before Christmas often sets the annual record for retail sales, vying with Thanksgiving weekend’s Black Friday. In recent years, last-minute shopping has determined the success of the season, and a relatively weak final weekend bodes poorly for retailers.

This year Super Saturday weekend sales in stores and online rose 4 percent to $55 billion, after a 2.5 percent gain last year, according to retail consultancy and private-equity fund Customer Growth Partners. That puts overall store and online sales from the start of November through Dec. 22 on track to rise 3.1 percent, below the 3.2 percent pace the firm forecast and down from 4.1 percent growth in the same period last year.

“Sales have been sluggish so far this year as most consumers are still buying close to need,” said Craig Johnson, president of Customer Growth Partners. “What’s worse is the marked deceleration from a year ago,” he said.

Last year, last-minute sales gained in the final 10 days of the holiday season, driven by savings from lower gasoline prices. If sales, spurred by gift card redemptions, hold up in the week after Christmas this year, retailers could move closer to meeting performance forecasts, consultants and retail experts said.

The National Retail Federation, the leading industry body, has forecast a 3.7 percent rise in store and online sales this year.

Discounts across categories have been deeper than last year, in the range of 20 percent to 50 percent, said Traci Gregorski, vice president of marketing at analytics firm Market Track. But consultants said the discounting still had not been enough to boost store traffic materially.

Shoppers take part in Black Friday Shopping at a Target store in Chicago, Illinois, United States, November 27, 2015. REUTERS/Jim Young

Promotions earlier in November took a toll on in-store sales during the Thanksgiving weekend, when total spending was the same as last year, according to the NRF.

The drop in store traffic has been offset to a large extent by online sales. Forrester expects U.S. households to spend $95.5 billion online during the holiday season, up 11 percent over last year. E-commerce accounts for 10 percent of U.S. retail spending annually, but 14 percent of spending during November and December, the company said.

The surge in online sales did not significantly disrupt services this year at delivery companies like United Parcel Service Inc and FedEx Corp, which put firm cut-off dates for gifts to ship in time for Christmas, the companies and consultants said.

Most retailers had little choice but to comply with the cut-off dates.

“We have stopped (free shipping) for orders that promised delivery by Christmas” because of UPS’ cut-off date, said Noelle Sadler, chief marketing officer at online clothing retailer Lulus.

WEAKER TRAFFIC

Analytics firm RetailNext, which tracks specialty stores like Best Buy Co Inc and large retailers like Wal-Mart Stores Inc and Target Corp, said sales dropped 6.7 percent over the pre-Christmas weekend compared with a year ago, and store traffic dipped 10.4 percent. However, customers who did hit the stores spent more.

“The jury is still out,” said Bridget Johns, head of customer engagement at RetailNext. “We still have over a week before the season closes but it will surely be a race to the finish line.”

Best-sellers during the holiday season have included toys and home improvement items like appliances, tools, furnishings and home decor.

But apparel sales plummeted as warm weather hurt sales of winter clothing and discounts on electronics hurt retail margins, even as sales volumes in the category remained robust.