Spring has finally sprung for US retailers after a combination of factors pulled together in March to lift same-store sales for the seventh month in a row.

"Everything from the weather to the calendar helped drive more shoppers into retail stores in March," said Frank Badillo, senior economist at consultancy and research firm Retail Forward.

An earlier Easter holiday, improved consumer confidence, and easy comparisons with last year also contributed to the 9.2% gain in March comps - more than doubling last month's 3.9% rise and the 4.7% drop in the same month a year ago.

March is also the first month when spring lines make a full appearance.

Among the winners were department store operators Kohl's and JC Penney, discounters Target and TJX, and teen retailer Aeropostale - all of which raised their earnings forecasts Thursday (8 April).

There was good news too from Gap Inc, the US' largest specialty clothing retailer, with an 11% rise in comps helped by growth across its US Gap, Old Navy and Banana Republic stores.

And luxury department stores Saks and Nordstrom both reported double-digit hikes in same-store sales.

But Abercrombie & Fitch and JC Penney fell short of analysts' estimates, even though their same-store sales rose in the month.

Crucially the results were strong across all formats, with Michael McNamara, vice president, research and analysis for SpendingPulse, noting that areas showing the largest year-on-year increases "were online sales and luxury retailers."

"In addition," he says, "all areas of apparel were also comfortably in positive territory."

The results are particularly good news for apparel firms since they show consumers are continuing to shop for discretionary items like clothing and make some of the purchases they avoided during the recession.

"Prices maintained their levels as inventories continued to be aligned with demand and retailers did not seem to have had to resort to discounting in order to drive traffic during the Easter shopping season," McNamara adds.

But of course it still remains to be seen whether this momentum continues, since the Easter boost to March revenues will likely come at the expense of April sales.

"There will be a letup in April, but sales should hold up better than might be expected given the ongoing recovery in spending plans by shoppers," Badillo added.

Even so, there's still a long way to go before sales levels return to the highs of 24 months ago.