内容摘要：The nation's eyes are on Hurricane Florence, which overcame some big odds to target the East Coast t

The nation's eyes are on Hurricane Florence, which overcame some big odds to target the East Coast this week.

Regardless of where the storm ultimately lands in the Carolinas, the Southeastern U.S. is due for potentially unprecedented rainfall and violent surges of ocean water.

SEE ALSO:Hurricane Florence replaced its eyewall. What does that mean?

"This is shaping up to be a very dangerous scenario, as Florence nears our coast and stalls, unprecedented, and life-threatening flooding may unfold," the National Weather Service in Wilmington, North Carolina, wrote Wednesday.

Here are five telling things to know as Hurricane Florence churns toward land:

1. The storm is growing

As of the morning of September 12, NASA found that the storm was 400 miles in diameter. That's more than the distance between Los Angeles and the Grand Canyon.

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It's growth has been aided by the formation of a new eyewall, which tends to increase the size of a hurricane, meaning that its extreme wind field stretches even farther than weaker storms.

The National Hurricane Center measured wind speeds of over 50 mph 100 miles out from Florence's center.

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2. The storm could break rainfall records

The National Hurricane Center is forecasting that Hurricane Florence will slow to a crawl just off the coast of the Carolinas.

Similar to Hurricane Harvey -- the largest rainfall event in U.S. history -- Florence could bring heavy, sustained rainfall over the Carolinas, delivering up to 40 inches in some areas, according to the National Weather Service (NWS).

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Projected rainfall totals form Hurricane Florence.Credit: noaa

This means catastrophic flooding.

As the NWS emphasizes, most hurricane deaths aren't from extreme winds, but moving water.

Historically, rainfall records from hurricanes have brought at most 24 inches of rain to North Carolina, in 1998. Florence has the potential to topple that record.

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Generally, rains will fall over a massive swath of land. The NWS predicts more than 5 inches of rain over a 570-mile long region.

3. Making giant waves

Although Carolina coastlines will be met with storm surges, out in the open ocean Florence is producing rather terrifying waves.

Wednesday morning, the National Hurricane Center measured wave heights of up to 83 feet in the Atlantic.

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4. Serious evacuations: Reverse driving on freeways

Many coastal areas in the Carolinas and Virginia are under mandatory evacuations.

To ease the heavy traffic leaving the coast, South Carolina reversed freeways lanes to allow traffic to flow away from the coming storm.

The video below shows the South Carolina Highway Patrol leading the public down reversed lanes.

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5. Florence isn't alone

It's the peak of hurricane season in the Atlantic, a time where warm ocean temperatures and diminished wind shear typically stoke the greatest number of hurricanes.

As of September 12, the Atlantic has three named storms (tropical storms with sustained winds of at least 39 mph), as well as two other weather patterns that could soon become well-organized storm systems.

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"If all 5 systems were to be named at the same time, it would be 1st time on record [the] Atlantic had 5 named storms simultaneously," according to a tweet from hurricane scientist Phil Klotzbach.

But for now, Florence is, rightfully, getting nearly all the attention.

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