Katrina helps wal-mart meet sale forecast

According to cnn.com Wal-Mart has reported that due to increased demands for hurricane-related items that it has meet its September sales forecasts. This is due to increase of sales in regions where residents where evacuated to. Wal-Mart says that its forecast is subject to impacts from hurricanes and rising oil prices. How does rising oil prices affect Wal-Mart? Will sales be lower for the next forecast?