Pending sales of previously owned homes rose to a record in August, indicating continued strength in the U.S. housing sector before Hurricane Katrina slammed into the Gulf Coast, data released Wednesday by the National Association of Realtors (search) showed.

The Pending Home Sales Index (search), based on data collected in August, hit a high of 129.5, up 3.2 percent from July and 4.7 percent higher than a year ago.

The previous record of 128.1 was posted in October 2004, the trade group said.

Pending home sales typically close within one to two months of signing, so the August increase in the index indicates that home sales may climb in September and October.

Still, disruptions in the areas most affected by Hurricane Katrina (search) may cast a shadow of the housing sector's strong performance, the Realtors group said.

"Home sales remain at remarkable levels, but there is ambiguity regarding pending home sales in parts of the South since many transactions in the disaster zone will be postponed," said David Lereah, the group's chief economist. "It's unclear how much of that disruption may be offset by spiking sales in surrounding areas."

Direct data from many hard-hit areas will be unavailable until multiple real estate listing services that have been affected are restored, the trade group said.