Don’t underestimate Hurricane Florence just because it’s been downgraded to a Category 2 storm.
That’s the message officials and experts are sending as the massive storm churns toward the Carolinas, where it’s expected to come ashore late Thursday or early Friday. The U.S. National Hurricane Center has downgraded the storm’s category twice after its wind speed dropped from a high of 225 km/h to 175 km/h early Thursday. It was previously a Category 4 storm.
“Just because the wind speeds came down, the intensity of the storm came down to a Category 2, do not let your guard down,” FEMA administrator Brock Long said at a briefing Thursday morning.
“This is a very dangerous storm,” Long said.
All hurricanes are ranked based on the Saffir-Simpson scale, which assigns a category from one to five based on wind speed. But the scale does not account for how much rain the storm will drop over an area, or how high the ocean will rise as it comes ashore in a storm surge.
“Ignore the category. You have to be concerned with the water and the storm surge,” said Athena Masson, a hurricane researcher with the University of Toronto.
Masson says she wants to “slap” anyone who lets down their guard in the Carolinas, just because the category has been downgraded.
“That’s just looking at the wind speed,” Masson told Global News on Thursday.
“Wind speeds are not the cause of the majority of the fatalities or the majority of the damage … It’s mostly the water.”
Masson says the storm has slowed down and expanded, so it’ll rain over a broader area and for a longer period than previously thought.
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“It truly is really about the whole size of the storm,” Ken Graham, director of the National Hurricane Center, told the Associated Press. “The larger and slower the storm is, the greater the threat and the impact — and we have that.”
The storm is expected to drop immense amounts of rain on the Carolinas and parts of Virginia and Georgia as it drifts inland over the next several days.
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“People are just not used to thinking about the rainfall as the hazard of a hurricane,” said Jessica Whitehead, a coastal communities hazard adaptation specialist for North Carolina Sea Grant.
“There are so many hazards from a hurricane,” she told Global News from her home outside Raleigh, N.C. on Thursday.
“It’s really the water that gets you. It’s the water that tends to kill people.”
Whitehead says many homes in the Carolinas are built to withstand intense winds, but they’re not prepared to deal with the damage caused by storm-surge flooding.
“We can build to code for wind, but getting things up off the ground for water is a challenge,” she said.
Masson says the storm surge threatens to push water far inland, backing up rivers and streams that regularly pour out into the ocean.
She compared Florence to Hurricane Sandy, which slowed from a Category 3 storm to a Category 2 before it hammered New York City on Oct. 29, 2012. The storm dumped massive amounts of rain on the region and triggered storm surges of over 13 feet.
“With Sandy, it was not the wind speed. It was the immense flooding and the immense storm surge,” she said. “Florence could easily follow the same track as Sandy.”
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Sandy has been blamed for a total of 185 deaths, including 60 in New York and New Jersey. Dozens were also killed in the Caribbean.
Whitehead says the storm category can be misleading because it oversimplifies the threat a storm poses to the public.
“Just because the winds have weakened doesn’t mean the storm has weakened,” she said.
More than one million people have been ordered to leave their homes ahead of the storm.
FEMA administrator Brock Long urged any stragglers on Thursday to leave while they still have a chance to do so.
“ storm surge is why many of you have been placed under evacuation,” he said.
“Your time is running out. The ocean is going to start rising.”
— With files from the Associated Press
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