Quarterly earnings at U.S. chains including Abercrombie & Fitch Co (ANF.N) and Ann Inc (ANN.N) took a big hit from deep discounts they offered to clear out clothes stocked for snow and cold that never came.

Both chains warned of weaker-than-expected earnings in the holiday quarter, sending shares of Abercrombie down nearly 12 percent and Ann down almost 8 percent on Thursday. Abercrombie also gave a forecast for this year's earnings that was well below analysts' estimates.

The lackluster forecasts coincided with a mixed bag of sales results from retailers in January, which showed a widening gap between those that are doing well and those that did not have the merchandise or deals that customers wanted during the holidays.

At Abercrombie, "the weather mismatch is problematic, but to us it looked like there was a lot of inventory that just did not move over the holiday season," Morningstar analyst Jaime Katz said.

The third-warmest January in 50 years was particularly cruel to department stores and apparel retailers, especially the ones that did not roll out spring items early to catch customers looking for warmer-weather fashions.

"Need-based purchases of cold weather apparel or snow removal items were difficult to find in January," said Scott Bernhardt, chief operating officer of Planalytics, which provides weather data for businesses.

Nonseasonal products accounted for most January purchases and gift card redemptions, he added.

Discounts at many apparel chains climbed to as much as 70 percent in January from the 40 percent level in late December as the retailers tried to clear their shelves off winter goods, Nomura analyst Paul Lejuez said earlier this week.

In particular, Abercrombie and Gap Inc's (GPS.N) Old Navy chain struggled to clear their shelves of outerwear, Lejuez noted.

Discounters such as Target Corp (TGT.N) and Costco Wholesale Corp (COST.O) as well as high-end stores Saks Inc (SKS.N) and Nordstrom Inc (JWN.N) beat expectations for January sales at stores open at least a year, while chains which cater more to middle-income shoppers and which sell more clothing were hurt the most.

Teen clothier Wet Seal Inc (WTSLA.O) and department store chain Bon-Ton Stores Inc (BONT.O) both came in below analysts' targets. Gap also reported a 4 percent fall in same-store sales, but the decline was not as steep as analysts had feared.

Overall, U.S. retailers reported a 4.2 percent rise in January same-store sales. Analysts had been a 2 percent rise, according to Thomson Reuters data, but they had been lowering their estimates coming into the month.

The Standard & Poor's Retail Index .RLX was up less than 0.1 percent at midday, in sync with the broader Standard & Poor's 500 Index .SPX.

NOT A GAME CHANGER

As to the January winners, Costco's better-than-expected 8 percent rise in same-store sales was helped by strong sales of food, small appliances and men's apparel. The warehouse club's comparable gasoline sales rose 15 percent, as members came to its pumps more often as prices rose.

Limited Brands Inc's (LTD.N) same-store sales rose 9 percent in January, while analysts expected a 2.7 percent rise. Driving the company's performance was Victoria's Secret, a brand that has resonated well with shoppers regardless of the vagaries of the economy or weather.

"Those are each sort of unique scenarios," said Ken Perkins, president of research firm Retail Metrics.

The smallest sales month of the year, January is mostly dedicated to clearance of carryover holiday goods, prompting many analysts to downplay the effect it will have on the consumer-driven U.S. economy.

Also, same-store sales reports capture only part of the retail economy. Wal-Mart Stores Inc (WMT.N) and other major retailers such as Best Buy Co Inc (BBY.N) and Amazon.com (AMZN.O) do not report monthly results.

"You don't want to change your perspective" based on January, said Michael Niemira, chief economist of the International Council of Shopping Centers, which expects February same-store sales to rise 3 percent to 3.5 percent.

(Reporting By Dhanya Skariachan in New York, Jessica Wohl and Nivedita Bhattacharjee in Chicago; Editing by Lisa Von Ahn)