U.S. single family home prices fell for the seventh straight month in January, bringing prices to just above April 2009 lows, a closely watched survey said on Tuesday.

The S&P/Case-Shiller composite index of 20 metropolitan areas declined 0.2 percent in January from December on a seasonally adjusted basis where a Reuters poll of economists forecast a drop of 0.4 percent. Prices in the 20 cities have fallen 3.1 percent year-over-year compared to 3.2 percent expected.

The housing market recession is not yet over, said David Blitzer, chairman of the index committee at S&P. At most, we have seen all statistics bounce along their troughs; at worst, the feared double-dip recession may be materializing.

Eleven of the 20 cities fell to the lowest levels since home prices peaked in 2006 and 2007, while the overall index was just 1.1 percent above the April 2009 low, the report showed.

Unadjusted for seasonal impact, home prices fell 1.0 percent for the month. Only San Diego and Washington, D.C. showed annual price increases.

The Case-Shiller index lags data from the National Association of Realtors, which reported earlier this month U.S. that the median U.S. home price had hit a nine year low in February as home sales volumes plunged 9.6 percent.

In a separate report, the realtors group on Monday said contracts for sales of previously owned U.S. homes rose 2.1 percent in February after two straight declines.

The pending contracts data leads existing home sales by a month or two and suggests some of the recent weakness was due to unusually severe winter weather.

(Reporting by Corbett B. Daly; Editing by Padraic Cassidy)