Top retail chains are set to report a jump in March sales, lifted by an early Easter, an improving job market and warm weather, in what may be the strongest sign yet that consumers are shopping again.

Several dozen of the largest U.S. retailers, from Saks Inc and Kohl's Corp to TJX Cos Inc and Target Corp are due to report this week sales at stores open for at least year, an industry gauge known as same-store sales.

Analysts, on average, are expecting same-store sales at those retailers to have increased by 6.2 percent in March, with heavily battered teen apparel chains showing some of the biggest improvements.

That would mark the seventh straight month of improving sales, according to Thomson Reuters data, and compares with a 5 percent decline a year ago.

Easter's early arrival on April 4 provided a major boost, as sales typically tick up two weeks ahead of the holiday and kick off spring shopping. In 2009, Easter fell on April 12.

Beyond the holiday effect, the results should make it clear whether shoppers are feeling better about spending as corporate layoffs ease and more signs point to economic growth.

It's not just an early Easter, it's that the consumer is rebounding, said Liz Dunn, an analyst at Thomas Weisel Partners. Last year there was a tremendous amount of fear ... and a feeling that you couldn't find a bottom.

People with jobs are generally more confident they will keep them and are hitting stores, Dunn said. The U.S. private sector created jobs in March at its fastest rate in three years.

The housing and stock markets are also performing well, easing concerns about home values and investment portfolios. Warm weather early in the month added to the positive sentiment following record snowstorms in February.

February was brutal, but as soon as the flowers started to come out and birds started to sing, the shoppers came out in full force, said Scott Bernhardt, the chief operating officer of Planalytics, which provides weather data for businesses.

Shares in the Standard & Poor's Retail index <.RLX> rose 1.2 percent on Monday, outpacing the wider market.

MARCH GAINS AT APRIL'S EXPENSE?

In an early look at March sales, drugstore operator Walgreen Co, on Monday posted a 2.3 percent same-store sales rise.

For investors, the one concern may be that March sales gains came at the expense of April results. Lazard Capital Markets analyst Todd Slater warned in a research note that share price gains may be overblown and could lead to a hangover in April.

But some analysts said shares in retailers that sell discretionary merchandise, like teen chains, could yet rise.

There's still upside left, said Dunn. The rebound in 2009 didn't take stocks back to 2006 levels- over the more medium term, I expect them to continue to go up.

Clothing stores that cater to teens are expected to show the most improved March sales performance, helped by easing unemployment among young job-seekers and a hike in allowances from their parents. Last year, the group saw some of the sharpest declines at the height of a consumer spending slump.

American Eagle Outfitters Inc and Aeropostale Inc are expected to lead the teen pack with gains of 10.4 percent and 10.7 percent, respectively. Abercrombie & Fitch Co , whose same-store sales plummeted 34 percent last year, is expected to post a rise of 6 percent.

A strong performance in teen apparel would bode well for an overall comeback, signaling that shoppers are buying more than just staples, said Jharonne Martis, director of consumer research at Thomson Reuters.

Analysts also credit retailers' for taking a careful look at how they stock shelves to have products shoppers want at the right time and allowing them to charge full price.

Merchandising is better and the timing of the fashions is better, said Richard Hastings, a consumer strategist at Global Hunter Securities.

Other retailers set to report large gains include department store operators Kohl's and upscale Nordstrom Inc , both of which gained market share in the crisis.

Kohl's is expected to report a 12.1 percent jump, compared to 7.6 percent for Macy's Inc and 5.7 percent for JC Penney Co Inc , while Nordstrom's expected 10.3 percent jump would best a forecast increase for Saks of 8.3 percent.

(Reporting by Phil Wahba; Editing by Michele Gershberg, Bernard Orr)