Hurricane Laura - Huge chemical fire spews toxic chlorine gas over Louisiana and at least four dead as Mike Pence is blasted for empty offer of prayers

Good morning and welcome to The Independent's live blog tracking the arrival of Hurricane Laura on the southern US coast.

We'll be following the latest updates as the storm, the most powerful to hit the US so far this year, is predicted to make landfall in the coming hours.

Hurricane Laura is blasting 150mph winds along the Gulf of Mexico as the storm strengthened close to a Category 5 approaching landfall along the Texas and Louisiana coasts, where residents are bracing for destructive winds and life-threatening surges with waves as high as two storeys.

The National Hurricane Centre clocked sustained winds of 150mph with even-stronger gusts as the storm gathered strength over the Gulf on Wednesday night.

The storm is expected to hit during high tide, and weather officials delivered an ominous forecast of an "unsurvivable" surge with "large and destructive" waves as high as 20 feet along the coast, and as far as 40 miles inland, that could "cause catastrophic damage".

"In the five years I've been governor, I don't believe I've had a press conference where it was my intention to convey the sense of urgency that I am trying to convey right now," Louisiana Governor John Bel Edwards said during a Wednesday briefing as he urged residents to make immediate and final storm plans. "Our state hasn't seen a storm surge like this in many, many decades."

A dire warning on Sunday told Louisiana residents that they have "until nightfall" to finish preparing for the storm or making plans to evacuate. "Wherever you are when it gets dark is where you should plan to be for 72 hours," message alerts told residents.

After noon on Wednesday, text alerts warned Louisiana residents that "if you've been told to evacuate, do so now."

Evacuation orders were in place in Texas and Louisiana for roughly 500,000 people, while buses of residents from western Louisiana headed to New Orleans, on the hurricane's eastern track. But it is understood that not everyone who was advised to evacuate has done so.

The National Oceanic and Atmospheric's Storm Prediction Centre issued a tornado watch extending across Louisiana and southeastern Texas, effective until 8am EST.

A storm surge warning also is in effect along the central Texas coast to the mouth of the Mississippi River in southeast Louisiana, while hurricane-force winds are expected along the Texas and Louisiana coasts through Thursday.

Areas to Laura's east and in its direct path will see the highest storm surges, while the National Hurricane Centre warned an "unsurvivable" surge could hit southwest Louisiana and its border along the upper Texas coast.

"Widespread" flash floods are expected in streets and waterways from eastern Texas into Louisiana and Arkansas, the Hurricane Centre reported.

Portion of Interstate 10 in Louisiana were closed from Lake Charles to Lafayette.

Laura is tracked to make landfall as a Category 4 with 140mph winds as the eye of the storm moves north towards Arkansas along the Texas and Louisiana borders.

The region has been battered by storms that have intensified with the climate crisis, with the erosion of protective marshlands, barrier islands and protective tree lines compromised by brackish water intrusion, while shipping lanes carved out by industry have stripped lines of defence from powerful storms.

The hurricane is threatening a centre of the US energy industry, and 84 per cent of Gulf oil production and an estimated 61 per cent of natural gas production has been shut down, with close to 300 platforms evacuated.

Laura has already killed nearly two dozen people on the island of Hispaniola, including 20 in Haiti and three in the Dominican Republic, where it knocked out power and caused intense flooding.

Read the full story on Laura's progress towards making landfall here:

Laura has begun moving over land with winds recorded above hurricane force to 110mph (177kph), the National Hurricane Center said.

The northern edge of the eye of the storm is now over Louisiana's Cameron parish, with forecasters warning that winds may still strengthen further, powerful enough to rip apart buildings and bring down trees.

The storm will officially have made landfall once the centre of the eye is over land - this is expected to happen soon.

In the coastal Cameron Parish, the district where Laura is making landfall in Louisiana, at least 150 people refused to evacuate before the storm's arrival.

That's despite officials predicting that a storm surge 20ft high - two storeys - will inundate most of the parish, a situation described by the state as "unsurvivable".

Officials went door to door in recent days urging roughly 7,000 residents to get out before the storm struck, as well as using social media posts and phone calls to warn of the danger. 

But Ashley Buller, assistant director of the parish Office of Emergency Preparedness, said officials knew of about 150 people who decided to stay put in structures ranging from seemingly safe elevated homes to recreational vehicles, which could easily be swept away by rushing storm surge.

"It's a very sad situation," Buller told AP from Lake Charles, where parish officials relocated from an office closer to the coast in Cameron. "We did everything we could to encourage them to leave."

Forecasters said Gulf waters could rise 20 feet along the coast of the low-lying parish without adding the height of waves, meaning the entire parish could be inundated. The storm is hitting at high tide.

Louisiana Governor John Bel Edwards said: "They're thinking Cameron Parish is going to look like an extension of the Gulf of Mexico for a couple of days."

Laura makes landfall

Hurricane Laura has made landfall, with the eye of the storm passing over land at 1am local time (CDT), the National Hurricane Center said. 

The Center said Laura arrived as a category 4 hurricane with maximum sustained winds of 150mph. It confirms its status as one of the most powerful storms ever to hit the state of Louisiana, and the strongest storm this year to hit the US.

Louisiana Governor says search and rescue operations will begin Thursday 

Louisiana Governor John Bel Edwards said search and rescue rescue efforts will start when officials are able to head out into the floodwaters safely. 

Speaking on the radio on Wednesday evening about the "apocalyptic" language being used to describe the storm, Gov Edwards said: "The language I've heard from the National Weather Service I've never heard before ... They're sending the strongest possible message about how serious this storm is."

He cited particular concern for Cameron Parish, the district in Louisiana where Laura is making landfall and which could experience a storm surge of up to 20 metres. 

Gov Edwards added that some buildings could be overwhelmed by the surge. 

State closing Interstate 10 due to expected flooding 

The Interstate 10 will shut from around Atchafalaya Bridge near Lafayette into Texas because of anticipated flooded, the governor of Louisiana has said. 

This comes amid fears that Laura will cause a storm surge of ocean water to travel far inland.  

David Roth, a forecaster at the National Weather Service, said: "This is one of the strongest storms storms to impact that section of coastline."

"We worry about that storm surge going so far inland there because it's basically all marshland north to Interstate 10. There is little to stop the water," he added. 

Laura poses threat to energy infrastructure, prompting environmental worries

There are concerns that Laura could damage oil industry sites located around the Gulf Coast, where almost half of the country's oil refining capacity is situated. 

In 2017, Storm Harvey led to oil and chemical spills as well as large scale air pollution from refineries.

Now, people worry Laura may cause similar environmental damage. 

"The storm and the direct damage and human life are the most important things, but pollution can be a double whammy and compound the risk to the community," said Luke Metzger, executive director of Environment Texas.

His comments came as refineries and natural gas terminals closed in Louisiana and Texas on Wednesday before the hurricane made landfall. 

Phillips 66 was among the energy companies to shut down its operations, both in the Lake Charles area and at a site in Beaumont, Texas.