The latest on a tropical weather system in the Gulf of Mexico (all times local):

Louisiana Gov. John Bel Edwards has asked the Trump administration for a federal declaration of emergency ahead of Tropical Storm Barry’s expected landfall late Friday or early Saturday along the state’s coast.

In a letter Thursday to President Donald Trump, Edwards asks that the state receive supplementary federal resources as soon as possible should they be needed. His letter notes that in the past 24 hours, 28 parishes have issued emergency declarations and 14 are in the process of completing such declarations.

Edwards says it is necessary that critical pre-positioning be provided through federal assistance.

Meanwhile, the Louisiana National Guard says Edwards has authorized activating up to 3,000 soldiers and airmen ahead of the storm. Officials say high-water vehicles and boats have been staged and helicopters are ready to support as needed.

A hurricane warning has been issued for parts of the Louisiana coast ahead of Tropical Storm Barry’s arrival.

The U.S. National Hurricane Center issued the warning Thursday afternoon for the Louisiana coast from Intracoastal City to Grand Isle. A tropical storm warning is in effect for other areas including the New Orleans metro area.

Barry is currently a tropical storm with winds of about 40 mph (65 kph), and was offshore about 90 miles (145 km) south of the mouth of the Mississippi River.

Forecasters say the storm is likely to become a Category 1 hurricane before making landfall Friday or early Saturday.

The Mississippi Emergency Management Agency is telling people in the southern part of the state to be prepared for heavy rain from Tropical Storm Barry as it pushes northward through the Gulf of Mexico.

The agency says people in low-lying areas should have a plan to evacuate before waters rise.

Forecasters say the storm could become a hurricane and make landfall in Louisiana. Effects could be felt in Mississippi by early Friday.

MEMA says there’s the potential for storm surge greater than 3 feet (1 meter) on the Mississippi Gulf Coast and the south and central parts of the state could have heavy rainfall and flooding.

Louisiana Gov. John Bel Edwards says authorities don’t expect the Mississippi River to overflow levees as Tropical Storm Barry moves toward the Gulf Coast.

At a Thursday news conference, the governor said high water forecasts for the river have gone down slightly but a change in the storm’s direction or intensity could renew the possibility of the levees being topped by a river already swollen by heavy rains and snow melt.

Forecasters say Barry could hit Louisiana as a weak hurricane over the weekend. Edwards said it would be the first time a hurricane made landfall in Louisiana when the Mississippi River was already at flood stage.

The mayor of New Orleans says the city’s water pumps are “working at optimal capacity” as Tropical Storm Barry moves toward the state’s Gulf coast.

But speaking at a Thursday news conference, New Orleans Mayor LaToya Cantrell added that flooding is a threat because slow-moving, heavy rains are expected from the storm.

National Weather Service meteorologist says New Orleans could get 10 to 15 inches (25 to 38 centimeters) of rain Friday, Saturday and Sunday. Some isolated areas could see 20 inches (50 centimeters).

Barry could hit Louisiana as a weak hurricane over the weekend.

Tropical Storm Barry has formed in the Gulf of Mexico and forecasters say it could become a hurricane as it threatens Louisiana’s coast.

The U.S. National Hurricane Center says the storm’s maximum sustained winds Thursday morning are near 40 mph (64 kph) with additional strengthening expected during the next day or two.

A tropical storm warning is now in effect for the Louisiana coast from the mouth of the Pearl River to Morgan City.

Plaquemines (PLAK-uh-minz) Parish spokeswoman Jade Duplessis says about 8,000 to 10,000 parish residents are under a mandatory evacuation order as a potential tropical storm brews in the Gulf of Mexico and half of them may need help.

All of the parish’s east bank and part of its west bank are under mandatory evacuation orders.

The parish government has set up pickup points on both sides of the Mississippi River. From there, school buses will take people to a registration point and then to evacuation centers.

Duplessis says cats and dogs will be taken in separate vehicles and if owners don’t have their own travel crates, the parish will provide them.

The evacuation order took effect at 6 a.m. Thursday. Duplessis says officials hope everyone is out by Friday afternoon.

The disturbance in the Gulf is expected to develop into a tropical storm late Thursday and could hit southern Louisiana as a weak hurricane this weekend.

The mayor of a barrier island town on Louisiana’s coast has ordered a mandatory evacuation as a potential tropical storm brews in the Gulf of Mexico.

Mayor David Camardelle’s order takes effect at noon Thursday on Grand Isle, which is accessible only by boat or a single flood-prone state highway.

Other low-lying areas of coastal Louisiana including the towns of Lafitte, Crown Point and Barataria also came under evacuation orders Thursday.

That follows similar orders Wednesday for parts of Plaquemines Parish,. The Mississippi River runs through the parish and could overtop some levees.

The disturbance in the Gulf is expected to develop into a tropical storm late Thursday and could hit southern Louisiana as a weak hurricane this weekend.

Carnival Cruise Line says it rerouted a cruise ship headed to New Orleans because of the potential tropical storm brewing in the Gulf of Mexico.

The Miami-based company says the more than 3,700-passenger Carnival Valor was sent to Mobile, Alabama, in the interest of safety. A company statement notes that coastal Louisiana is under a hurricane watch and water levels are high on the Mississippi River.

Mobile Mayor Sandy Stimpson tweeted a welcome to Valor passengers and a photo of the ship docked in Mobile on Thursday.

Carnival says arriving passengers will be taken from Mobile to New Orleans on complimentary buses.

The ship was supposed to depart Thursday from New Orleans on its next four-day cruise to Cozumel, Mexico. Instead, passengers will be taken to Mobile by bus from New Orleans.

A potential tropical storm brewing in the Gulf of Mexico presents twin troubles for parts of southeast Louisiana.

It could contribute to the rising of an already high Mississippi River, with water reaching the tops of levees this weekend. And there is also the widespread danger of flash floods like the one that walloped New Orleans on Wednesday. Officials said that storm dumped as much as 8 inches (20 centimeters) in parts of the metro area in three hours.

The Gulf disturbance that spawned the floods was forecast to strengthen into a tropical storm by Thursday night.

Forecasters said Louisiana could see up to 12 inches (30 centimeters) of rain by Monday. Some areas could get 18 inches (46 centimeters).

Mississippi and Texas were also at risk of torrential rains. </s> Louisiana residents are bracing for a possible hurricane as Tropical Storm Barry continues to threaten the state’s coast.

Mandatory evacuations were issued for parts of Louisiana on Thursday — specifically in Plaquemines Parish where — as of Thursday morning — 8,000 to 10,000 parish residents were under a mandatory evacuation order, spokeswoman Jade Duplessis said.

Barry, which is the second named storm of the Atlantic hurricane season, is expected to strengthen into a hurricane by late Friday and make landfall by early Saturday along the Louisiana coast.

The National Weather Service also warned flooding is a threat as New Orleans could get 10 to 15 inches of rain Friday, Saturday and Sunday. Some isolated areas could see 20 inches. Storm surges watches and warnings are also in effect for various areas along the coast.

Read on for a look at the storm’s expected path and other information.

Where is Tropical Storm Barry now?

The National Hurricane Center said in a 1:00 p.m. update on Thursday that the slow-moving storm is located about 90 miles south of the mouth of the Mississippi River. It noted the storm is “moving slowly westward across the northern Gulf of Mexico,” and warned “dangerous storm surge, heavy rains and wind conditions [are] expected across the north-central Gulf Coast.”

As of that same time, Tropical Storm Barry had maximum sustained winds of 40 mph.

How is the state preparing?

On Wednesday, Louisiana Gov. John Bel Edwards declared a state of emergency for all of Louisiana.

"This is going to be a Louisiana event with coastal flooding and widespread, heavy rainfall potentially impacting every part of the state,” Edwards said in a statement. “No one should take this storm lightly. As we know all too well in Louisiana, low intensity does not necessarily mean low impact.”

The governor also encouraged residents to “check [their] emergency supplies and get a game plan for [their] family and pets. He also urged residents to monitor local media for “weather developments and follow the directions of local officials.”

HURRICANE HEALTH RISKS: 3 THINGS TO WATCH OUT FOR

New Orleans Mayor LaToya Cantrell said the city's water pumps are "working at optimal capacity" as Tropical Storm Barry moves toward the state's Gulf coast. That said, at a Thursday news conference, she added that flooding is a threat because slow-moving, heavy rains are expected from the storm.

“We cannot pump our way out of the water levels ... that are expected to hit the city of New Orleans,” she warned.

Fox News' Travis Fedschun and The Associated Press contributed to this report. </s> Louisiana authorities are urging residents not to underestimate the danger and destruction Tropical Storm Barry threatens as it nears the coast Friday.

“Look, there are three ways that Louisiana floods: storm surge, high rivers and rain. We’re going to have all three,” Gov. John Bel Edwards said Thursday in a news conference.

Barry is getting stronger as it creeps across the Gulf of Mexico’s warm waters en route to a landfall expected early Saturday in Louisiana.

While it could reach hurricane strength, the real peril it poses to roughly 10 million people in its path is rain, which could quickly trigger unprecedented flooding.

Ten to 15 more inches of rain are on the way, CNN meteorologist Derek Van Dam said, threatening to inundate ground already soaked from a Wednesday storm that flooded some New Orleans homes and businesses.

Meantime, another risk looms in the Mississippi River. Usually at 6 to 8 feet this time of year around the Big Easy, the river is at 16 feet after a year of record flooding, and Barry could push in a storm surge of 2 to 3 feet.

Officials are “confident that there will not be overtopping of the levees in New Orleans,” Edwards told CNN Friday. Still, the unusual confluence of factors is rattling nerves along the “sliver by the river,” a swath of relatively high ground along the Mississippi that’s less likely to flood in typical rain and hurricane storm surge events than other areas.

At 8 a.m. ET Friday, Barry was 95 miles southwest of the mouth of the Mississippi River with maximum sustained winds of 50 mph. About 800,000 people are under a hurricane warning along the Louisiana coast from south of Lafayette to south of New Orleans.

Barry is the first storm of the 2019 season to approach the United States.

Stocking up or moving out

President Donald Trump has declared a state of emergency for Louisiana, where officials activated 3,000 National Guard members in anticipation of the destruction Barry might bring, the governor said.

“Heed the warnings,” he told CNN’s John Berman on Friday morning, pointing out that fatalities often happen when motorists try to drive through floodwater.

“It’s deeper than they believe it to be, and also there’s current that sometimes is imperceptible,” Edwards said. “We need individuals to not drive through standing water.”

While some in low-lying places have been directed to evacuate, officials haven’t ordered mandatory evacuations in the most populated areas.

Many residents aren’t eager to endure the expense and effort of leaving, compared with what could be a few uncomfortable hours or days without power. Many also want to stay home so they can bail water if it rises, then dry out floors and drywall as soon as it recedes.

Pamela Hughes will ride out the storm in her mother’s trailer in Port Sulphur, which is under a mandatory evacuation order, she said.

“I really don’t think it’s going to be too bad,” she told CNN.

Others, including Kristopher Williams, are staying behind to protect their pets and their belongings.

“Everything I own is in it,” he said of his truck. “I’m not an ignorant person. I know the dangers. I also know how to get out of just about any bind I encounter.”

As others head to higher ground, Chef José Andrés’ nonprofit World Central Kitchen announced Thursday it would set up kitchens in Lafayette and New Orleans ahead of the storm.

New Orleans’ network of drainage pumps, underground pipes and canals were overwhelmed earlier this week by rain. And though water piled up briefly on some streets, the storm was a good test of the drainage system, Edwards said.

“It performed well,” he said, adding, “you never know exactly what Mother Nature’s going to throw at you. … But I’m confident that New Orleans is going to weather this storm (Barry) in pretty good fashion.”

Flooding concerns are not limited to Louisiana. Mississippi, Alabama and the western Florida Panhandle are also at risk for extreme rain, CNN meteorologist Haley Brink said Thursday.

Mobile, Alabama, can expect heavy rain that may lead to flash flooding, as well as a high risk of rip currents and a surf up to 8 feet, the National Weather Service tweeted early Friday.

The Florida Panhandle has seen double red flags go up in some areas, closing beaches, the weather service said.

The Mississippi Delta Region is also at risk for tornadoes beginning Friday evening. </s> NEW ORLEANS (AP) — Louisiana Gov. John Bel Edwards issued an emergency declaration Thursday, preparing the state for the possibility of flooding rains from Texas-bound Hurricane Harvey.

"This is a very serious storm," Edwards said at a news conference in Baton Rouge.

Forecasters said the center of Harvey, which reached hurricane strength Thursday, was expected to hit the Texas coast Friday or early Saturday. Heavy rains are expected to extend into Louisiana as its winds spin counter-clockwise, carrying water from the Gulf of Mexico far inland.

National Weather Service forecasts had rainfall amounts as high as 15 inches in southwest Louisiana over the next seven days, and up to six inches in the New Orleans area.

"It could be a lot more. It could be next to nothing," Barry Keim, the state climatologist at LSU, said in a telephone interview. "There's potential for some very, very big rains, depending on the track of the storm."

Edwards, who dealt with disastrous storm flooding in parts of south Louisiana just over a year ago, was accompanied by Maj. Gen. Glenn Curtis, head of the Louisiana National Guard, who said the state has positioned six boats and 15 high-water vehicles in the New Orleans area and can dispatch more to other parts of the state if needed.

In New Orleans, where flash floods Aug. 5 exposed numerous problems with the pumps and pipes that remove floodwaters, Mayor Mitch Landrieu said improvements have been made and are ongoing.

"We remain in a state of diminished draining capacity," Landrieu said. He said capacity has been increased since those recent floods and that 105 of 120 pumps are working. He also noted that intense and prolonged rain can flood parts of New Orleans even when the system is at full strength.

When heavy rain two weeks ago flooded streets and buildings in parts of the city, initial statements by city officials that pumps were working at full capacity turned out to be false. Not only were some pumps out of service, there were problems with a turbine that generates power for the system.

The head of the city's Sewerage and Water Board has since resigned, and a six-member emergency team is overseeing improvements.

 _ </s> NEW ORLEANS (AP) — Tropical Storm Barry's wind and rain began hitting parts of Louisiana Friday as New Orleans and coastal communities braced for a drenching from what could be the season's first hurricane.

A hurricane warning was in effect along the Louisiana coast, with forecasters predicting landfall as a hurricane by early Saturday.

The storm's rains are expected to pose a severe test of New Orleans' improved post-Katrina flood defenses . Barry is forecast to bring more than a foot and a half (0.5 meters) of rain to parts of the state as it moves slowly inland.

"There are three ways that Louisiana can flood: storm surge, high rivers and rain," Louisiana Gov. John Bel Edwards said. "We're going to have all three."

Edwards warned of a dangerous combination with the already-high Mississippi River, which has been swelled by heavy rain and snowmelt upriver this spring. He said authorities do not expect the river to spill over its levees, but cautioned that a change in the storm's direction or intensity could alter that.

National Hurricane Center Director Ken Graham said pockets of Louisiana could have as much as 25 inches (63 centimeters) of rain.

"So here's the takeaway: Dangerous situation," he said during an online presentation Thursday. "That kind of rainfall in this system could cause flash flooding, cause ponding of water."

National Guard troops and rescue crews were stationed around the state with boats and high-water vehicles. Helicopters were also on standby, and supplies including drinking water and blankets were ready for distribution, the Guard said.

President Donald Trump on Thursday night declared a federal declaration of emergency for Louisiana, authorizing the Department of Homeland Security and Federal Emergency Management Agency to coordinate all disaster relief efforts.

Barry could have winds of about 75 mph (120 kph), just barely over the 74 mph threshold for a hurricane , when it comes ashore, making it a Category 1 storm. Forecasters said Friday morning that while their models don't "explicitly show Barry becoming a hurricane, it is still possible for that to occur before landfall."

As of early Friday, Barry was about 80 miles (130 kilometers) south of the mouth of the Mississippi, with winds around 50 mph (80 kph). Tracking forecasts showed the brunt of the storm blowing into the Louisiana delta west of New Orleans on a path that could continue toward Chicago, swelling the Mississippi River basin with water that must eventually flow south again.

Louisiana's low-lying southeastern tip was getting hit first. Many heeded evacuation orders affecting 10,000 people in Plaquemines Parish, leaving communities largely empty by Thursday afternoon.

Among the last to leave the town of Phoenix was 65-year-old Clarence Brocks and his family. The Plaquemines Parish native has evacuated many times and had to rebuild after Katrina wiped out his home. But he said that he wouldn't want to live anywhere else, despite the yearly threat of hurricanes.

"I was born and raised here. This is all I know," the Air Force veteran said. "I've been all over the world and guess where I want to be at? Right here."

Jesse Schaffer III of Meraux (MEE-roh) in St. Bernard Parish to the north was helping his relatives in Plaquemines Parish get to family members' houses in safer areas. He said around 20 relatives were staying with him and his wife because their house is safer.

"We're trying to evacuate and get all of our family members up and go to St. Bernard Parish," he said.

With lightning flashing in the distance and some streets already covered with water from heavy rains, shoppers at an Albertsons grocery store in Baton Rouge stripped shelves bare of bread by Thursday night. Half the shelves normally filled with bottled water were empty.

A radar loop of Barry filled a TV screen at a brewery near downtown. Nearby, the sign outside a convenience store read: "Barry needs a beer and a nap."

Meanwhile, utility crews with bucket trucks that could be needed after the storm filled hotel parking lots along Interstate 59 in southern Mississippi.

The National Hurricane Center said as much as 20 inches (50 centimeters) of rain could fall in parts of eastern Louisiana, including Baton Rouge, and the entire region could get as much as 10 inches (25 centimeters). The New Orleans area could get 10 to 15 inches (25 to 38 centimeters) through Sunday, forecasters said.

New Orleans Mayor LaToya Cantrell said Thursday that the pumping system that drains the city's streets is working as designed but that Barry could dump water faster than the pumps can move it.

"We cannot pump our way out of the water levels ... that are expected to hit the city of New Orleans," she warned.

However, the city did not plan to order evacuations because Barry was so close and because it was not expected to grow into a major hurricane. Officials instead advised people to keep at least three days of supplies on hand and to keep their neighborhood storm drains clear so water can move quickly.

Hurricane Katrina caused catastrophic flooding in New Orleans in 2005 and was blamed altogether for more than 1,800 deaths in Louisiana and other states, by some estimates.

In its aftermath, the Army Corps of Engineers began a multibillion-dollar hurricane-protection system that isn't complete. The work included repairs and improvements to some 350 miles (560 kilometers) of levees and more than 70 pump stations that are used to remove floodwaters.

Associated Press reporters Chevel Johnson and Rebecca Santana in New Orleans, Sarah Blake Morgan in Plaquemines Parish and Jay Reeves in Baton Rouge contributed to this report. </s> Tropical Storm Barry forms in Gulf, could become hurricane

NEW ORLEANS (AP) — Tropical Storm Barry formed off the coast of Louisiana on Thursday and threatened to blow ashore as a hurricane with relatively weak winds but torrential rains that could test the flood-control improvements made in New Orleans since Hurricane Katrina 14 years ago.

Forecasters said the first hurricane of the Atlantic season could hit the state's swampy southern tip Friday night or early Saturday, with potentially ruinous downpours that could go on for hours as the storm passes through the metropolitan area of nearly 1.3 million people and pushes inland.

Plaquemines Parish, at Louisiana's low-lying southeastern tip, ordered the mandatory evacuation of as many as 10,000 people, and communities began handing out sandbags. Louisiana Gov. John Bel Edwards declared an emergency and said National Guard troops and high-water vehicles will be positioned all over the state.

"The entire coast of Louisiana is at play in this storm," he warned.

On Wednesday, with the gathering storm still out over the Gulf of Mexico, it dumped as much as 8 inches (20 centimeters) on metro New Orleans in just three hours. The deluge triggered flash flooding in the city's streets and raised fears about the even heavier rains on the way.

The National Hurricane Center said as much as 20 inches (50 centimeters) of rain could fall in parts of eastern Louisiana, including Baton Rouge, and the entire region could get as much as 10 inches (25 centimeters). The New Orleans area could get 10 to 15 inches (25 to 38 centimeters) through Sunday, forecasters said.

The storm's surge also could prevent water from emptying out of the already-swollen Mississippi River, possibly sending water over levees near New Orleans, forecasters said. The river has been running high for months.

Barry could have winds of about 75 mph (120 kph), just over the 74 mph threshold for a hurricane, when it comes ashore, making it a Category 1 storm, forecasters said.

National Weather Service meteorologist Benjamin Schott said the big concern is water, not wind: "Rainfall and flooding is going to be the No. 1 threat with this storm."

New Orleans Mayor LaToya Cantrell said that the pumping system that drains the city's streets is working as designed but that the slow-moving storm could dump water faster than the pumps can move it.

"We cannot pump our way out of the water levels ... that are expected to hit the city of New Orleans," she warned.

However, the city did not plan to order evacuations because the storm was so close and because it was not expected to grow into a major hurricane. Officials instead advised people to keep at least three days of supplies on hand and to keep their neighborhood storm drains clear so water can move quickly.

Katrina caused catastrophic flooding in New Orleans in 2005 and was blamed altogether for more than 1,800 deaths in Louisiana and other states.

In its aftermath, the Army Corps of Engineers began a multibillion-dollar hurricane-protection system that isn't yet complete. The work included repairs and improvements to some 350 miles (563.24 kilometers) of levees and more than 70 pump stations that are used to remove floodwaters.

The weather service said it expects the Mississippi to rise to 19 feet (5.8 meters) by Saturday morning at a key gauge in the New Orleans area, which is protected by levees 20 to 25 feet (6 to 7.6 meters) high.

"We're confident the levees themselves are in good shape. The big focus is height," Corps spokesman Ricky Boyett said.

In Plaquemines Parish, Justice of the Peace David McGaha waited with his mother, his wife and their 15-year-old son and 11-year-old daughter for a ferry so they could evacuate to his mother's house in Alabama.

"If the river wasn't so high, we'd probably stay. You have to worry about the water that'll be pushing against those levees," he said. "They made a lot of improvements to the levee, but they haven't completed all the projects."

Associated Press reporters Chevel Johnson and Janet McConnaughey contributed to this report from New Orleans. </s> The first tropical system to slam the US this year lashed parts of the Deep South with heavy rains Thursday morning as it spins through the Gulf of Mexico.

More than 4 million people are under flash flood watches from south-central Louisiana to the western Florida panhandle as the system moves over the warm waters, CNN meteorologist Haley Brink said.

If it reaches winds of 39 mph, it will officially become Tropical Storm Barry and could intensify into a Category 1 hurricane by late Friday. The storm had maximum sustained winds of 30 mph Thursday, and is expected to make landfall along the Louisiana or upper Texas coast Saturday.

But even before it reaches tropical storm status, it’ll deluge the Gulf Coast region with heavy rains, leading to flash flooding that could cause the Mississippi River to rise to dangerous levels.

Southern Louisiana, Mississippi and Alabama, along with the western Florida Panhandle, will especially get drenched Thursday, Brink said.

Governors to residents: Prepare and stock up

As the tropical system strengthens, regional leaders are urging people in the area not to get caught off guard.

“Begin preparing your property, your supplies, your lines of communication to your family members,” Texas Gov. Greg Abbott said. “Begin preparing to know exactly where you need to go if you need to evacuate.”

The governor said the state has high-water rescue boat squads ready to help, CNN affiliate KEYE reported.

In Louisiana, Gov. John Bel Edwards declared a state of emergency and asked residents to have a contingency plan for family and pets. About 10 to 15 inches of rain could fall within 24 hours between Friday and Saturday, he said.

“This is going to be a Louisiana event with coastal flooding and heavy rainfall potentially impacting every part of the state,” he said. “No one should take this storm lightly. As we know all too well in Louisiana, low intensity does not necessarily mean low impact.”

New Orleans got a taste of the tropical system after it spawned its first tornado warning and flash flood emergency in the area Wednesday. It dumped up to 9 inches of rain in parts of the city, flooding streets, homes and hotel lobbies.

The slow-moving storm was crawling at 9 mph Thursday morning, and was 125 miles southeast of the mouth of the Mississippi River, the National Hurricane Center said.

That means it could hover over the same place for long time, dumping rain relentlessly. Storm surge, hurricane force winds and extensive flooding are forecast in the Gulf Coast region into the weekend.

The potential storm surge has prompted the National Weather Service to warn that the Mississippi River could crest at 20 feet in New Orleans, or 1.3 feet below the record. The city is protected to a height of 20 feet.

Louisiana officials started closing flood gates over concerns that the storm surge could cause additional flooding. More than 200 flood gates in Orleans and St. Bernard parishes are expected to be closed by Friday, local media reported. </s> If there is one thing you need to know about Tropical Storm Barry, it is this: The storm bearing down on Louisiana is forecast to be a flooding disaster.

Basically every aspect of the setup for Barry is lined up to unleash multiple types of flooding that could last for days on end, potentially placing the flooding on par with Hurricanes Florence and Harvey. The Gulf Coast from the Florida Panhandle to Louisiana is covered in a panoply of flood warnings from the National Weather Service. The variety and extent could expand in the coming days as Barry gathers strength and its path becomes more clear.

The reason for Barry’s prolific flood forecast has very little to do with its official strength. While the category it reaches on the Saffir-Simpson scale as its winds speed up will be the primary way Barry is defined meteorologically, the rainfall and storm surge will define how much damage this storm does.

Rain, which is expected to begin in earnest on Saturday, is the biggest concern, with Barry forecast to drop 10-15 inches of rain over a wide area of Louisiana and Mississippi and locally higher amounts of 20 inches or more possible. That would be bad news enough. An unnamed storm dumped more than 20 inches of rain across a large portion of Louisiana in August 2016, causing $10 billion in damage. Baton Rouge was particularly hard-hit as rain hammered the state capital.

Barry may not match the exact rainfall totals from that storm, which topped 31 inches, but the rain that does fall will do so on already swollen rivers and soggy land that can’t hold an iota more water. That can lead to two types of flooding: your standard but still terrible standing water floods, and flash floods with rushing water that can wash away cars, people, and infrastructure in their path. Both already racked New Orleans and the surrounding area on Wednesday, which is in part why everything is so soggy ahead of Barry.



The timing of Barry is also particularly bad from a river flood perspective. The Mississippi River is still shuttling record-setting spring floodwater from the Midwest to the Gulf of Mexico. The high state of the river coupled with an approaching hurricane “would be the first time we’ve had the hurricane hit the state with rising rivers” according to a tweet from Louisiana Governor John Bel Edwards.

“Hurricanes/tropical storms usually impact Louisiana later in the season,” Hal Needham, a hurricane expert and founder of Marine Weather and Climate, told Earther in an email. “Barry is arriving earlier and encountering Mississippi River levels that are high.”

Any rain that falls will engorge the river further, and could threaten to overtop levees in New Orleans. If that happens—or if a levee fails—the result would be catastrophic for the city. And that brings us to yet another type of flood the Gulf Coast could see. As floodwaters rush down rivers and creeks toward the Gulf of Mexico, they’ll run into a wall of saltwater trying to come up as Barry plows inland.

Barry’s storm surge is expected to be relatively minor compared to, say, Hurricane Michael from last year, because the storm is likely to be smaller and less organized, according to Needham. But Barry will raise water levels along the coast and push at least some surge inland, essentially damming freshwater coming downstream in place and leading to something known as compound flooding. Something similar happened during Hurricane Florence last year where water levels stayed elevated even after the storm had passed.

“Even if a community is not flooded by saltwater, elevated salt water levels along the coast can contribute to flooding by slowing the drainage process,” Needham said.

This whole setup also neatly illustrates how climate change and the way we’ve developed can create overlapping risks that will only increase in the coming decades. Heavy precipitation events like the ones that inundated the Midwest this spring and are now clogging the Mississippi River in Louisiana are becoming more common in every corner of the U.S. The warmer atmosphere human carbon pollution has created simply holds more water, leading to more prolific downpours. While no research has been done to attribute any aspect of Barry to climate change, the expected heavy rain also certainly fits that pattern. And attribution research for Harvey two years ago showed that climate change did increase the odds of the storm’s record-setting rainfall.

At the same time, the infrastructure we rely on has also added to the flooding woes we’re facing today. In Houston, for example, paving over the prairie grass that used to absorb floodwaters with concrete that accelerates runoff and keeps waters aboveground contributed to Harvey-related woes. Ditto for New Orleans, which is partly located below sea level and relies on a series of levees largely built in the 20th century. And with days of rain ahead, we’re about to see if last century’s protections can keep this century’s water at bay. </s> How are you preparing for Tropical Storm Barry? When it's safe, you can text, iMessage or WhatsApp your videos, photos and stories to CNN at +1 347-322-0415

(CNN) Samantha Kincaid was forced to evacuate during Hurricane Gustav in 2008, her first year in New Orleans. Now, she's leaving again.

This week's widespread flooding in New Orleans ahead of a slow-moving storm system made her uneasy, she told CNN in a Facebook message.

"Being stuck in the flood and then waiting for the waters to go down was a real wake up call," said Kincaid, who made plans Thursday to head to west to Lafayette. "I was lucky to not have my car stall out."

As a dangerous weather system spinning toward the Gulf coast intensified Thursday to become Tropical Storm Barry, some Louisiana residents aren't taking any chances and are choosing to evacuate. Others say they plan to ride the storm out.

Barry is the first tropical storm to threaten the United States this year. The forecast shows it as a tropical storm at landfall, possibly by Saturday morning on the Louisiana coast, probably west of New Orleans. There is a significant chance that Barry could be a hurricane, with sustained winds of 74 miles per hour, when it makes landfall.

But it's not the wind that makes this storm so treacherous. It's the colossal rainfall and massive storm surge.

"This is a life-threatening situation," the National Hurricane Center said. Those in the storm's path should "take all necessary actions to protect life and property from rising water and the potential for other dangerous conditions."

Streets in New Orleans turned into lakes after getting pummeled with up to 9 inches of rain Wednesday -- a day before the system was declared a tropical storm.

The Broadmoor neighborhood in New Orleans was flooded Wednesday.

Whether to stay or whether to go

Claire Hartley Grogan of New Orleans said she too was preparing to evacuate. She will probably head toward Florida and have a "hurrication."

The Mississippi River was too high, and she was scared to stay.

"My entire life, I have lived blocks from the Mississippi River and not been scared. Today, and for the last month or so, [I] have been terrified," she said.

Pamela Hughes said she will ride out the storm in her mother's trailer in Port Sulphur, south of New Orleans in Plaquemines Parish, which is under a mandatory evacuation order.

But Hughes said she knows the risk and is staying, even though the trailer isn't on high ground.

"I really don't think it's going to be too bad," she said.

Hughes says she's prepared with gas, food and water. She said the levels of the Mississippi River near Port Sulphur, and the nearby bayou, look low to her.

But Hughes said she evacuated her mother, who has breast cancer and recently got out of the hospital.

As of late Thursday, Barry was hurling winds of 50 mph in the Gulf of Mexico, but it's expected to continue to intensify, the National Hurricane Center said.

Because Barry is a slow-moving storm -- crawling across the Gulf at just 3 mph -- it will hover over the same places for a long time, dropping relentless rain and adding to widespread flooding.

The National Hurricane Center issued hurricane warnings for the Louisiana coast from Intracoastal City to Grand Isle.

The mayor and town council in Grand Isle, on a barrier island the Gulf of Mexico, ordered everyone to evacuate Thursday.

"We are expecting a rain fall total that can range from 6" to 10"," they said in a statement. "We will be experiencing unusual high tides that will range more than 3 feet above ground."

Baton Rouge, which is northwest of New Orleans, is expected to get 10 to 15 inches of rain. Resident Rusty Miller said that his experience with previous storm evacuations taught him to hunker down and hope the electricity stays on. He is staying put for now. But this time, he said, he's worried about flooding.

"As long as this thing doesn't stall, we should be fine," Miller said.

Mississippi, Alabama and the western Florida Panhandle are also at risk for extreme rain, CNN meteorologist Haley Brink said Thursday.

An unprecedented challenge

Barry will inundate Louisiana at a terrible time: when rivers like the Mississippi are already extremely high.

"This is the 258th day of a flood fight on the Mississippi River," Gov. John Bel Edwards said Thursday.

Unusually high river levels will lead to an unprecedented challenge when Barry makes landfall.

"This is the first time we've had a tropical system with water levels on the river this high," said Jeffrey Graschel, a hydrologist with the National Weather Service's Lower Mississippi River Forecast Center.

In New Orleans, the Mississippi River was more than 16 feet high on Thursday. At this time of year, it should be more like 6 to 8 feet, Graschel said.

In the coming days, the river could crest at 19 feet, 1 foot lower than previously forecast. But the bloated river is still risky, because New Orleans is protected only to a height of 20 feet.

In preparation for the onslaught, Louisiana officials have started closing floodgates. The Southeast Louisiana Flood Protection Authority has about 250 floodgates, spokesman Antwan Harris said.

More than 200 floodgates in Orleans and St. Bernard parishes are expected to be closed by Friday to protect the area from the expected storm surge, local media reported.

Louisiana's governor warned that "no one should take this storm lightly," as 10 to 15 inches of rain could fall within 24 hours between Friday and Saturday.

The governor sent a letter to President Donald Trump requesting a federal declaration of emergency as the storm approached.

He also declared a state of emergency and urged residents to have a contingency plan for family and pets.

The US Postal Service temporarily relocated operations to other parts of the state due to mandatory evacuations.

'The calm before the storm'

In one part of New Orleans, some residents have remained calm.

Heather Cafarella, a bartender at R Bar, said people didn't appear to be panicking. She asking each other if they're going to evacuate is almost like asking "how's the weather?"

"It's not just the hurricane. We flood when there's heavy rain. It doesn't take much, unfortunately," Cafarella, 41, said.

She glanced outside at a sunny, dry street. "The calm before the storm is so deceiving," she said.
Louisiana Governor John Bel Edwards declares a state of emergency as Tropical Storm Barry makes unprecedented levels of rainfall on Louisiana, Mississippi, Alabama and the western Florida Panhandle.