(CNN) You can't tell from looking at the streets still under water, but the Gulf Coast got lucky with this storm.

Barry, which made landfall as a hurricane Saturday, quickly turned into a tropical storm and has been inundating Louisiana ever since.

A couple walks through a flooded street Sunday in Mandeville, Louisiana.

Even as a weaker tropical depression Monday, Barry is still dumping heavy rain on parts of Louisiana, Mississippi and Arkansas, prompting a wave of new flash flood watches.

But fears of devastating storm surges and catastrophic flooding didn't materialize. There are a few reasons for that, CNN meteorologist Dave Hennen said.

"The storm surge in the populated areas like New Orleans didn't rise to the level to cause major problems," he said. "That being said, there was surge to 7 feet in a few areas, which was actually higher than forecast."

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