The first tropical system to slam the US this year is expected to make landfall as a hurricane. But days before landfall, it's already walloping New Orleans with widespread flooding.
The National Hurricane Center predicts Tropical Storm Barry will form in the Gulf of Mexico by Thursday and strengthen to a hurricane by Saturday, when it's expected to make landfall in Louisiana.
The tropical system has already spawned its first tornado warning and flash flood emergency, both in the New Orleans area.
New Orleans resident Angela Catalano, whose house is already flooded, said she's worried about what's next.
'We took in about 2 feet of water in our basement/ground floor level,' Catalano said. 'I'm very concerned about the impending storm, with the Mississippi River near flood stage. I'm very worried about more flooding.'
Indeed, the worst is yet to come. Louisiana Gov. John Bel Edwards said about 10 to 15 inches of rain could fall within 24 hours between Friday and Saturday.
'That is a short time period for such an intense' rainfall, Edwards said.
Even worse: The slow-moving storm is crawling at about 3 to 5 mph, the governor said. That means it could hover over the same place for long time, dumping rain relentlessly.
Forecasters warned drivers to stay off flooded roads.
'A FLASH FLOOD EMERGENCY has been issued for Jefferson Parish! 4 to 6 inches have already fallen and 2 - 3 more is anticipated,' the National Weather Service's New Orleans office tweeted. 'Please do not drive in flooded roads! Seek higher ground if flooding!'
New Orleans City Hall closed Wednesday as the ferocious weather kept pounding the city.
'As always during hurricane season, residents are reminded to review emergency plans, gather emergency supplies, and stay informed,' Mayor LaToya Cantrell's office said. 'Hurricane preparedness information is available at ready.nola.gov/hurricane.'
Warm water will fuel the storm's intensity
Residents from Houston to Mobile, Alabama, are bracing for the system's wrath.
As the low-pressure system moves closer to land, will meet warm, open waters that will fuel the storm's intensity, CNN meteorologist Haley Brink said.
A tropical storm is an area of thunderstorms that produces a circular wind flow with winds from 39 to 73 miles per hour. With a lower wind speed, it would be a tropical depression. Higher, and it would be a hurricane.
Regardless of the classification this system develops into, both Louisiana and Mississippi are forecast to see very heavy rain -- more than a foot in some places, Brink said.
Some oil rigs in the Gulf of Mexico have been evacuated.
Shell has evacuated all non-essential staff from eastern Gulf drilling rigs, with more action on the horizon depending on how the storm develops, spokeswoman Cindy Babski said.
Chevron has also evacuated some non-essential employees from the Jack St. Malo facility, with shut-in procedures initiated at five other facilities, spokeswoman Veronica Flores-Paniagua said.
The Mississippi River could crest at 19 feet
Potential storm surge has prompted the National Weather Service to issue a flood warning for the Mississippi River, including at New Orleans, through Saturday.
The NWS said the river could crest at 19 feet, or 2.3 feet below the record. The city is protected to a height of 20 feet.
The Flood Protection Authority said it will be closing several flood gates and structures in the New Orleans area starting Wednesday.
'No one should take this storm lightly,' Gov. Edwards said.