Forecasts generally project the storm to make landfall in southeast North Carolina as a Category 3 or 4 Thursday into Friday, although shifts in the track are possible and storm impacts will expand great distances beyond where landfall occurs.

AD

The National Hurricane Center is warning of a triple threat in the Carolinas and Virginia:

A “life-threatening storm surge” at the coast — a rise in ocean water over normally dry land. “Life-threatening freshwater flooding from a prolonged and exceptionally heavy rainfall event” from the coast to interior sections. “Damaging hurricane-force winds” at the coast and some distance inland.

Like Hurricane Harvey, which stalled over Texas in 2017, Florence could linger over the Southeast for several days after landfall, unloading 15 to 25 inches of rain and isolated amounts of up to 35 inches. The Hurricane Center said this is “likely” to produce catastrophic flash flooding.

The flooding might be similar to or worse than what the Carolinas experienced during Hurricane Matthew in 2016.

AD

“This will likely be the storm of a lifetime for portions of the Carolina coast, and that’s saying a lot given the impacts we’ve seen from Hurricanes Diana, Hugo, Fran, Bonnie, Floyd, and Matthew,” wrote the meteorologist on duty for the National Weather Service office serving Wilmington, N.C. “I can’t emphasize enough the potential for unbelievable damage from wind, storm surge, and inland flooding with this storm.”

AD

More than 1.5 million people have been ordered to evacuate coastal areas ahead of the storm, due to both destructive winds and the storm surge, which could place normally dry land under at least 10 feet of water.

“All interests from South Carolina into the Mid-Atlantic region should ensure they have their hurricane plan in place and follow any advice given by local officials,” the Hurricane Center said.

AD

The latest

News

“Even if you’ve ridden out storms before, this one is different,” North Carolina Gov. Roy Cooper (D) said at a Tuesday afternoon news conference, where he announced the mandatory evacuation of the state’s popular and fragile barrier islands. “It’s an extremely dangerous, life-threatening, historic hurricane,” he said, noting the forecast for days and days of rain.

AD

Federal officials warned that the millions in Florence’s sights could be without electricity for weeks, if high winds down power lines and massive rainfall floods equipment. There are 16 nuclear reactors in the region, and crews at the one closest to where landfall is forecast readied the station, at Brunswick, for a shutdown, said officials for the operator, Duke Electric.

Even before South Carolina’s mandatory evacuation order for coastal areas took effect at noon, cameras showed traffic at a crawl on the main interstate connecting Charleston and Columbia. In North Carolina, Dare County officials warned that ocean overwash already was spilling onto low-lying roads and slowing evacuations there.

AD

The monstrous storm has forced the closing of hundreds of schools throughout the region. Because Florence’s rainfall is expected to pound areas far from the coast, the University of North Carolina at Chapel Hill and Duke and North Carolina State universities canceled classes through week’s end. Boeing and Volvo shut down their Charleston factories, idling thousands who build 787s and sedans. South Carolina’s governor has ordered more than 1 million people living along the state’s coast to evacuate the area ahead of Hurricane Florence.

AD

In Virginia, officials said inland flooding was likely to be catastrophic and could test the James River flood walls in Richmond, the state capital. The Navy commander of the Mid-Atlantic region authorized an emergency evacuation order for personnel who live in the low-lying area under mandatory evacuation, and corrections officials said they had evacuated a prison in that area. The mayor of the District of Columbia joined Maryland’s governor in declaring an emergency in the nation’s capital.

President Trump has approved emergency disaster declarations for the Carolinas and Virginia, which frees up funds for relief and recovery. “We’re as ready as anybody has ever been,” he said after a briefing with Federal Emergency Management Agency Administrator William “Brock” Long and Homeland Security Secretary Kirstjen Nielsen.

He also canceled campaign rallies in Cape Girardeau, Mo., and in Mississippi.

AD

AD

“Florence could be the most dangerous storm in the history of the Carolinas,” Long, a North Carolina native, tweeted Tuesday.

Weather

As of 11 p.m., Florence’s top winds were 140 mph, and it was charging west-northwest at 17 mph, about 725 miles east-southeast of Cape Fear, N.C.

The Hurricane Center predicts its maximum winds could still reach 155 mph at peak intensity on Wednesday, which is just 2 mph from Category 5. Some modest weakening may occur just before landfall, but Florence is predicted to approach the coast as a Category 3 or 4.

The storm’s zone of hurricane-force winds expanded Tuesday and extends 60 miles from the center, while tropical-storm-force winds extend 175 miles outward.

Hurricane warnings were issued for the South Santee River, in South Carolina, to Duck, N.C., and Albemarle and Pamlico sounds. This includes Wilmington, N.C. Hurricane watches extended north to the North Carolina/Virginia border and south to the South Santee River, including the Charleston area.

Storm timing

In coastal areas of the Southeast and Mid-Atlantic, heavy surf and elevated water levels are expected to arrive by Wednesday morning, and rainfall could begin by late Wednesday night and Thursday morning. The rain is then predicted to spread inland by Friday and potentially continue for days as the storm slows or stalls.

AD

AD

Tropical-storm-force winds could reach the coastline as early as Thursday morning, at which point all outdoor preparations should be completed.

Extremely dangerous hurricane-force winds could batter coastal locations by Friday. Hurricane-to-tropical-storm-force winds could extend well inland, depending on the storm’s track.

Storm hazards

Storm surge

Like a bulldozer, the storm’s winds and forward motion will push a tremendous amount of water onshore when it makes landfall. The storm surge, or rise in water above normally dry land at the coast, could reach up to more than a story high, or 13 feet, if the maximum surge coincides with high tide.

Jeff Masters, the meteorologist who writes Weather Underground’s Category 6 blog, reported a maximum surge of 15 to 20 feet is possible, which would rival heights from hurricanes Hugo (1989) and Hazel (1954).

AD

AD

The biggest surge should occur just to the north of where the eye of the storm comes ashore, which the Hurricane Center projects in southeast North Carolina.

The surge will result in inundation of roads, homes and businesses.

Storm surge warnings were issued from South Santee River in South Carolina to Duck, N.C. The Charleston area is under a storm surge watch.

The Hurricane Center projects the following surge heights above normally dry land, if the maximum surge coincides with high tide:

Cape Fear to Cape Lookout, including the Neuse and Pamlico Rivers: 9 to 13 feet

North Myrtle Beach to Cape Fear: 6 to 9 feet

Cape Lookout to Ocracoke Inlet: 6 to 9 feet

South Santee River to North Myrtle Beach: 4 to 6 feet

Ocracoke Inlet to North Carolina/Virginia Border: 4 to 6 feet

Edisto Beach to South Santee River: 2 to 4 feet

Rain

Models have come into agreement that a northward turn before reaching the United States is unlikely and that a building high-pressure zone north of the storm will cause it to slow or stall once it reaches the coast or shortly thereafter. Where exactly the zone of heaviest rain will be is a big uncertainty. It could reasonably occur anywhere between coastal zones of southeast North Carolina and the mountains of southwest Virginia.

If the storm stalls, some areas could see feet of rain. The latest forecast models suggest the heaviest rainfall may focus in southeast North Carolina.

If the storm drifts into Virginia, this region will be particularly susceptible to flooding because of far-above-normal rainfall in the region since May. In addition, because the ground is likely to be saturated, trees will be vulnerable in strong winds.

Parts of the Mid-Atlantic, especially from Virginia to Pennsylvania, have received 150 to 300 percent of their normal rainfall since May.

Wind

AD

AD

The strongest winds will occur where and when the storm makes landfall in a ring around the calm eye of the storm known as the eyewall. If the storm makes landfall as a Category 4, these winds will be destructive, sustained at up to 130 mph or so with higher gusts.

The zone where these intense winds occur will be narrow, but the effects will probably be devastating, similar to a strong tornado. The Hurricane Center describes the types of damage associated with Category 4 winds:

Well-built framed homes can sustain severe damage with loss of most of the roof structure and/or some exterior walls. Most trees will be snapped or uprooted and power poles downed. Fallen trees and power poles will isolate residential areas. Power outages will last weeks to possibly months. Most of the area will be uninhabitable for weeks or months.

Outside this zone of destructive winds, damaging winds are still likely, even some distance inland from the coast, which will lead to minor structural damage, downed trees and widespread power outages.

A power outage model run at the University of Michigan projects that 3.3 million customers will be without electricity because of the storm, mostly in the eastern half of North Carolina.

AD

If the storm stalls in the eastern Carolinas as or just after the storm makes landfall, these wind impacts will be magnified.

The latest path projections

Where the storm makes landfall has implications for where the strongest winds and biggest rise in water at the coast occurs, but strong winds and extreme rainfall could occur at great distances from the landfall location. Keeping this in mind, here is the likelihood of landfall at different locations based on our evaluation of model data:

80 percent in the Carolinas

10 percent offshore

5 percent between North Florida and Georgia

5 percent north of the Carolinas

Even in the unlikely event that the storm center remains just offshore, it will almost certainly come close enough to bring dangerous wind and flooding to coastal areas. Areas farther to the north and west may be somewhat spared in this scenario.

While it is extremely likely that the eastern Carolinas will be hard hit by the storm Thursday into Friday, the storm’s direction becomes far less certain thereafter.

“Models are indicating that the steering currents will collapse by Friday when Florence is approaching the southeast U.S. coast,” the Hurricane Center wrote. “The weak steering currents are expected to continue through the weekend, which makes the forecast track on days 3-5 quite uncertain.”

Florence’s place in history

If Florence makes landfall as a Category 4 in North Carolina, it would be the strongest storm to come ashore that far north on record.

If a major hurricane (Category 3 or higher) does make landfall along the Southeast coast north of Florida, the rarity of such an event is relevant. Since 1851, only 10 major hurricanes have done so, and the most recent was Fran in 1996, 22 years ago. Hugo in 1989 was the one before that and was a Category 4 at landfall. No hurricane has made landfall as a Category 5 in this region on record.

Many people in the Southeast and Mid-Atlantic probably have not experienced a storm of the potential magnitude of Florence.

Tropical Storm Florence churns along the coast of the Carolinas share Share View Photos View Photos Next Image NEW BERN, NC - SEPTEMBER 15: A section of the Highway 17 exit ramp remains closed a day after Hurricane Florence's storm surge washed it out September 15, 2018 in New Bern, North Carolina.Hurricane Florence made landfall in North Carolina as a Category 1 storm Friday and at least five deaths have been attributed to the storm, which continues to produce heavy rain and strong winds extending out nearly 200 miles. (Chip Somodevilla/Getty Images)

Read more