The second leg in the much feared double dip in home prices is beginning to turn up on the year-over-year chart of the S&P/Case-Shiller Home Price Index, suggesting it will prove a far more shallow decline than the first leg that ran from late 2005 until 2009.

The Home Price Indices, released Tuesday, showed a second consecutive month of increase in prices for the 10- and 20-City Composites, which were up 1.1% and 1.0%, respectively, in May from April. Sixteen of the 20 markets measured posted positive monthly increases, with only Detroit, Las Vegas and Tampa down and Phoenix flat.

Prices as measured by the two composite indices were at levels comparable to summer, 2003.

"We see some seasonal improvements with May's data," said David M. Blitzer, chairman of the Index Committee at S&P Indices. "The concern is that much of the monthly gains are only seasonal."

Blitzer said the price data, combined with recent reports on housing starts, existing home sales and credit market reports, "support a continuation of the 'bounce-along-the-bottom' scenario we have witnessed in the housing market over the past two years." He added, "Sustained increases in home prices over several months and better annual results need to be seen before we can confirm real estate market recovery."

Washington D.C. continued to lead all markets in price gains, up 2.4% from April and 1.3% from last May to an index of 184.90, meaning prices there are nearly 85% above the baseline price set in January, 2000. Boston saw a 2.7% month-to-month jump but remained 3.2% behind last May with an index of 150.98. Minneapolis was up 2.6% sequentially but down 11.7% year-over-year at 108.34. San Francisco gained 1.8% but was down 5.4% on an annual basis at 134.42. Chicago more than reversed an April decline with a gain of 1.7% in May but remains 8.1% behind May 2010 with an index of 112.01.

Among other rising markets were Atlanta (index 102.85), up 1% sequentially and and down 4.6% year-over-year, respectively; Charlotte (110.44), up 0.8% but down 5.1%, respectively; Cleveland (98.88), up 1.3% and down 6.6% ; Dallas (114.31), up 0.9% and down 4.7%; Denver (124.00), up 1.4% and down 3.3%; Los Angeles (169.07), up 0.5% and down 3.2%; Miami (138.60), up 1.2% and down 5.3%; New York (164.96), up 0.7% but down 3.2%; Portland (134.50), up 1.2% and down 9.1%; San Diego (154.78), up 0.2% and down 5.1%; and Seattle (136.56), up 1.1% and down 7.0%.

Declining markets included Detroit, where the index fell to 62.01 on a 2.8% month-to-month decline and a 9.3% drop from May of last year; Las Vegas (95.60), down 0.9% and down 6.6%, respectively; and Tampa (125.10), down 0.6% and 9.5%. Phoenix, where prices measured by the index (100.4) have now fallen back to 2000 levels, was flat month-to-month and down 9.5% on an annual basis.