Nellie Doneva, Associated Press
Holiday shoppers navigate through Target in Abilene, Texas, last year. Many retailers have suffered a weak fall shopping season.

NEW YORK — Holiday sales are expected to grow at the slowest pace in six years as shoppers worry about jobs, the housing and stock markets and high gas and food prices, according to a forecast from the National Retail Federation being released today.

The outlook from the retail trade group joins other weak holiday predictions issued so far that will likely lead to aggressive discounting and pre-Thanksgiving sales blitzes as stores try to pry dollars from frugal shoppers.

Merchants have also scaled back holiday inventories and seasonal sales staff from a year ago. The challenges are compounded by a holiday season that has five fewer days between Thanksgiving and Christmas Day than in 2007, which could make consumers delay their buying.

"You don't have a good picture," said Rosalind Wells, the NRF's chief economist. Last week's financial turbulence, "only increases the uncertainty and anxiety," she said. Wells said she doesn't expect an economic turnaround until the second half of next year.

The Washington-based trade association predicted that total holiday sales will rise a modest 2.2 percent for the November and December period from a year ago, to $470.4 billion. That would be below the 10-year average of 4.4 percent holiday sales growth and a bit below the 2.4 percent gain last year. It would also be the slowest pace since 1.3 percent in 2002.

Total retail sales figures from the NRF exclude business from auto dealers, gas stations, and restaurants. The estimate also excludes online sales and reflects last week's financial turmoil, Wells said.

Two other forecasts, from Deloitte LLP and TNS Retail Forward, that were made before the recent market turbulence had predicted the weakest holiday growth since 1991 — though they use different metrics.

Deloitte LLP expects total holiday sales — including online sales — to rise 2.5 percent to 3 percent in the November through January period, less than last year's 3.4 percent gain. A rise of 2.5 percent to 2.8 percent in that period would be the smallest gain since 1991, Deloitte noted.

TNS Retail Forward, a global market information group, sees retail sales rising 1.5 percent in the October through December period, the weakest performance since 1991.

The downbeat forecasts come as many retailers have already suffered from a weak fall shopping season.