In many ways, this summer has been defined by floods.

From the deadly July 4th deluge in central Texas to countless other torrential downpours across the country, the reality of a warming world has been on full display.

But 20 years ago this week, water was wreaking havoc on the Gulf Coast.

Good evening, Hurricane Katrina, one of the most powerful and dangerous hurricanes ever on record,

slammed into the Gulf Coast this morning with winds as high as 140 miles per hour.

Parts of New Orleans and Mobile have been flooded with many

other communities also underwater. And the water continues to rise. A levy break the size of a football

field is slowly flooding New Orleans. Huge sandbags are being airlifted in to stem the flood.

Hurricane Katrina killed nearly 1,400 people and displaced more than a million others across the Gulf Coast.

It remains the costliest natural disaster in U.S. history.

It would also become an enduring symbol of government failure.

No food, no water helicopters flying over here.

It's ridiculous.

New Orleans is hot.

We can't take this.

We've been out here for three days.

And we've been asking for help.

For days, the black community in New Orleans felt abandoned, left to fend for themselves.

The mayor at one point has just told people there are no more buses to evacuate them

out, just get to the highway and start walking out of the city.

We have never seen anything like this in the United States of America.

Despite the outrage, President George W. Bush infamously praised his FEMA director, Michael Brown,

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