UPDATE 1-J.C. Penney same-store sales up 2.6 pct

(Updates with details, share activity, changes dateline from previous CHICAGO)

NEW YORK, Jan 4 (Reuters) - J.C. Penney Co. Inc. (JCP.N) said on Thursday its December sales at department stores open at least a year rose 2.6 percent, driven by sales of children's clothing and jewelry.

The result matched analysts' average expectation, according to a Reuters survey. J.C. Penney itself had forecast a low-single-digit increase.

The Plano, Texas-based company said total department store sales rose 4.2 percent to $2.96 billion in the five weeks ended Dec. 30.

Sales on its Web site rose 15.2 percent in December, while catalog and outlet stores' sales fell 1.4 percent.

The company saw strong sales in the week before and after Christmas in the last-minute "redbox gifts" category, but sweaters, outerwear and home products like bedding and window covers did not sell very well, said J.C. Penney spokesman Ed Merritt in a prerecorded telephone message.

Unusually warm weather this season has been blamed for lackluster sales by many retailers.

"We believe that through stores, catalog and jcp.com we have further strengthened our position as a one stop destination for all our customers' needs," Merritt said.

The company forecast a low-single-digit increase in January sales, and said it expected direct sales to slip slightly.

Shares of the company were trading down 58 cents to $77.48 in morning trading on the New York Stock Exchange.