Hurricane Laura is forecast to rapidly power up into a “catastrophic” Category 4 hurricane, even stronger than previously expected, as it churns toward Texas and Louisiana, gathering wind and water that swirls over much of the Gulf of Mexico.

Satellite images show that Laura has become “a formidable hurricane” in recent hours, threatening to smash homes and sink entire communities. It has undergone a remarkable intensification, “and there are no signs it will stop soon,” the National Hurricane Center said in an update early Wednesday.

“Some areas when they wake up Thursday morning, they’re not going to believe what happened,” Stacy Stewart, a senior hurricane specialist at the hurricane center, said Wednesday.

“We could see storm surge heights more than 15 feet in some areas,” Stewart said. “What doesn’t get blown down by the wind could easily get knocked down by the rising ocean waters pushing well inland.”

Laura has grown nearly 70% in power in just 24 hours, with maximum sustained winds increasing to 110 mph (175 kph) with higher gusts, forecasters said early Wednesday.

“We are expecting widespread power outages, trees down. Homes and businesses will be damaged,” said Donald Jones, a National Weather Service meteorologist in Lake Charles, Louisiana, which is near the bullseye of Laura’s forecast track.

“I’m telling you, this is going to be a very serious situation,” Jones said.

A Category 4 hurricane will do catastrophic damage: “Power outages will last weeks to possibly months. Most of the area will be uninhabitable for weeks or months,” the weather service says.

Stocks fell on Wednesday as traders grew worried about the increasing number of newly confirmed coronavirus cases, which raised concern about the economic reopening and recovery.

The Dow Jones Industrial Average dropped 500 points, or 1.9%. The S&P 500 traded 1.7% lower while the Nasdaq Composite slid 1.4%. The tech-heavy Nasdaq was headed for its first daily decline in nine sessions.

The major averages hit their lows of the day after Bloomberg News released headlines signaling a rise in Florida’s Covid-19 hospitalization rate along with a rise in the state’s number of confirmed cases.

“Markets pause with all eyes on the virus and the reopening heading into the summer months,” said Gregory Faranello, head of U.S. rates trading at AmeriVet Securities, in a note.  The health side is back front and center as both monetary and fiscal liquidity has been factored in short-term. We have entered a new phase of this crisis.”

A CNBC analysis of Johns Hopkins University data found the U.S. 7-day average of coronavirus cases surged more than 30% from a week ago after the total number of cases grew by more than 31,000 on Monday. California is one of the states that has seen a dramatic spike in cases, adding more than 6,000 on Monday alone. In Texas, the Covid-19 hospitalization rate has hit a record for 12 straight days. “We’re going to eclipse the totals in April, so we’ll eclipse 37,000 diagnosed infections a day,” former Food and Drug Administration Commissioner Dr. Scott Gottlieb told CNBC’s “Squawk Box.” “But in April we were only diagnosing 1 in 10 to 1 in 20 infections, so those 37,000 infections represented probably half a million infections at the peak.”

Overseas, Germany reported a cluster of newly confirmed cases at a slaughter house in Lower Saxony. That’s the latest in a series of coronavirus outbreaks in Germany. Shares of companies primed to benefit from the economy reopening faltered. United Airlines fell 5.9%. Delta, American and Southwest all slid over 4%. Carnival, Norwegian Cruise Line and Royal Caribbean were lower by 9.7%, 10.9% and 10%, respectively. Retailer Gap also fell 8%. Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said Tuesday the U.S. is seeing a “disturbing” surge in new Covid-19 cases.“This raises many questions but the most important is the policy direction,” said Tom Lee, head of research at Fundstrat Global Advisors, regarding the spike in cases. “We still see positive risk/reward in stocks and as we have said for some time, equities are in the hands of buyers.” Lee added that if the S&P 500 can stay above its 76% retracement levels, new highs will be hit this summer.