Storm in Gulf of Mexico has officially become Tropical Storm Barry, and is expected to become hurricane

The storm dumped as much as eight inches of rain in three hours over parts of New Orleans on Wednesday  

Major flooding and potential storm surge prompted Louisiana Gov Bel Edwards to declare state of emergency

New Orleans' historic French Quarter was also significantly flooded by the storm along Royal Street

The Mississippi River is forecast to crest at highest level since 1927 this weekend - more than 90 years

Mandatory evacuation issued 6am Thursday for as many as 10,000 people in Plaquemines Parish in Louisiana

Storm is set to deposit between 10 to 15 inches of rain on Gulf Coast from west Texas, through Louisiana coast

New Orleans has been hit by devastating storms before, including 2005's Hurricane Katrina which killed 1,833