* Home prices rise for 7th month in a row
* Stock markets closed in wake of storm
NEW YORK, Oct 30 (Reuters) - U.S. home prices gained further traction in August, the latest sign that the housing market is on the mend, a closely watched survey showed on Tuesday.
The S&P/Case Shiller composite index of 20 metropolitan areas gained 0.5 percent on a seasonally adjusted basis, in line with economists' forecasts.
It was the seventh straight month of increases, extending the longest continuous string of gains since prices were boosted by the homebuyer tax credit in 2009 and 2010.
The stabilization in home prices this year, along with a rise in sales and tighter inventories, has pointed to a housing market that is finally turning the corner, six years after its far-reaching collapse.
``The improvements we've seen are very sustainable and very solid,'' said Russell Price, senior economist at Ameriprise Financial in Detroit. ``They're on very firm footing in the housing market.''
On a non-seasonally adjusted basis, prices fared better, gaining 0.9 percent.
Prices in the 20 cities climbed 2 percent year-over-year, topping expectations for a 1.9 percent increase.
The U.S. stock market was closed for a second day in a row in the wake of a powerful storm that hit the east coast. Overall, the impact of the storm to the economy is expected to be short-term.
The sustained good news in home prices ``makes us optimistic for continued recovery in the housing market,'' David Blitzer, chairman of the index committee at S&P Dow Jones Indices, said in a statement.
``Even as we end the seasonally strong home buying period, the statistics are positive,'' said Blitzer.
Compared to a year ago, prices in Phoenix surged 18.8 percent, the fourth month in a row the hard-hit city has seen double-digit yearly gains, the report said. Phoenix has been one of the standouts this year as prices have snapped back.
Prices in Las Vegas - also one of the more distressed areas in the years since the end of the housing boom - were up 0.9 percent compared to a year ago, the first annual increase since January 2007.
Of the 20 cities in the index, three saw a yearly decline in prices, with Atlanta faring the worst, down 6.1 percent.
``Housing has a pretty solid footing, but some pockets of the country still have problems,'' said Craig Dismuke, chief economic strategist with Vining Sparks in Memphis, Tennessee.
Data on consumer confidence from the Conference Board had also been scheduled to be released on Tuesday but was pushed back to Nov. 1 in light of the storm.