Sales of previously owned U.S. homes fell for the third straight month in February, pushing sales down to the lowest level since July 2009, according to a trade group report on Tuesday that underscored the fragile nature of the housing market's recovery.

The National Association of Realtors said sales of previously occupied homes dropped 0.6 percent month-over-month to an annual rate of 5.02 million units in February. The poor sales further depressed prices with the median home price falling almost 2 percent from a February 2009 to $165,100.

Sales activity showed mixed results as Midwest sales increased3 percent, and Northeast sales improved more than 2 percent. Sales in the South dropped about 1 percent, and West’s sales fell 5 percent.

Last month, the inventory of unsold homes surged to 3.59 million increasing by 312,000 units or and pushing the inventory of unsold homes at 8.6 months at current sales pace. The inventory of unsold existing homes was 7.8 months in January

Yun said February storms in the East were a big factor to the sales decline. “Some closings were simply postponed by winter storms, but buyers couldn’t get out to look at homes in some areas and that should negatively impact near-term contract activity,” he said in a statement.

“Although sales have been higher than year-ago levels for eight straight months and home prices are much more stable compared to the past few years, the housing recovery is fragile at the moment.”

A NAR survey showed first-time buyers purchased 42 percent of homes in February, up from 40 percent in January. Investors accounted for 19 percent of transactions in February, compared with 17 percent in January; the remaining sales were to repeat buyers.

There is an $8,000 credit for first-time buyers and a $6,500 credit for current homeowners who have lived in their property for the past five years.