Getting strengthened with astonishing speed into a Classification four storm Wednesday, Hurricane Laura will make landfall in Texas and Louisiana someday early Thursday early morning. With the landfall arrives a dreaded storm surge—a rise in drinking water degree generated by a storm—that researchers say could unfold seawater up to thirty miles inland, an inundation the National Hurricane Centre just named “unsurvivable.”

The surge will be specifically hazardous together the coast, but it will keep on being a danger as the drinking water moves inland. “You have incredibly huge currents, incredibly huge and hazardous waves rather considerably inland together the instant coastline,” states Brian Zachry, Joint Hurricane Testbed director at the National Hurricane Centre. “And if you are conversing about a surge of 15 to 20 ft with incredibly huge waves, you just cannot endure that.”

“Even if you go inland,” Zachry adds, “as drinking water will get about the tops of banking institutions of rivers and other estuaries and this sort of, that drinking water can also have some velocity to it. As you see in flash flooding from rainfall, you can get swept away in that.”

For context, 2005’s Hurricane Katrina, a Classification five storm, experienced an eighteen- to 23-foot storm surge. “This storm seems like it will be similar as considerably as the amounts of storm surge that we are viewing,” states Mike Chesterfield, a meteorologist at the Weather Channel.

The size of a hurricane’s storm surge is dependent on a range of factors, “which tends to make the prediction of storm surge hard right up until shut to landfall,” writes Katie Peek, a coastal exploration scientist at Western Carolina College, in an electronic mail to WIRED. This involves wind speeds, how quickly the storm by itself is transferring, and atmospheric pressure. “Where a storm tends to make landfall is also crucial, as shallower waters offshore and the form of the coast perform a portion as perfectly,” Peek writes. “In the scenario of Laura, the storm is transferring through warm, shallow waters and projected to make landfall near an embayment (the shoreline is concave like a bowl) which can induce the waters to additional ‘pile up’ together the shore.”

And it is not just the point that the hurricane’s winds are pushing drinking water horizontally onto shore—the storm actually lifts the drinking water vertically. “In the heart of a hurricane, you get extremely very low pressures, which actually enables a little bubble to kind beneath the hurricane,” states Chesterfield. “The winds appear and decide up that drinking water and just pile it up on land. It is really a more compact variable when as opposed to wind, but it absolutely does perform a purpose.”

Not serving to issues is the point that warm water—which is specifically warm in the Gulf of Mexico right now—physically expands, getting up much more area than cold drinking water. And this storm could arrive through higher tide, which might also insert a little bit to the surge.

That could indicate a veritable wall of drinking water barreling inland, overpowering anything in its route. “Storm surge by itself is and does keep on being the deadliest part of hurricanes,” states Chesterfield. “If you set your self in a problem in which there is even ten ft of storm surge, odds of you obtaining out in one piece are fairly modest. But when you get up to 20 ft, there is no house construction, in any case, that is going to hold you safe and sound.”

This is specifically problematic in which Laura could hit—in very low-lying parts of Louisiana like the modest cities of Houma and Morgan City. And across the state’s coast, inlets and river channels can carry the drinking water farther inland. “You’re on the swamp, fundamentally,” states Jeremy Porter, head of exploration and progress at 1st Street Basis, which analyzes flood threat in the United States. Little cities are not perfectly suited to fend off a storm surge like this. “They just really don’t have the infrastructure, because they are much less populated,” Porter adds. “So there is threat in owning a great deal of populace, but there is also threat of not, because you really don’t have the tax base to make the infrastructure to actually shield your self from these styles of activities.”