NEW YORK, United States — J.C. Penney Co. shares jumped as much as 8.4 percent after Piper Jaffray Cos. predicted that sales will rebound this quarter, helped by warmer weather and an improved assortment of kids' clothing.

Neely Tamminga, an analyst at Piper Jaffray in Minneapolis, raised her same-store sales estimate to 3 percent from 1 percent for the first quarter. Including e-commerce, the sales will gain 3.9 percent, she said in a report on Tuesday.

The outlook helped renew investor optimism after the company delivered a disappointing forecast last month and sent its shares tumbling. J.C. Penney’s management also has been in flux. Chief Executive Officer Myron Ullman said in November that he would hand over the reins to former Home Depot Inc. executive Marvin Ellison in August. Chief Marketing Officer Debra Berman and General Counsel Janet Dhillon, meanwhile, both left the department-store chain earlier this month.

The shares climbed as high as $8.49 as of 3:27 p.m. Tuesday in New York, the biggest intraday gain in more than two months. Through yesterday, the stock was down 11 percent over the past 12 months.

Tamminga, who also said that Apple Inc.’s new smartwatch will help bring consumers to shopping malls next month, has the equivalent of a buy rating on J.C. Penney’s stock.

By: Nick Turner; editors: Nick Turner and James Callan.