Hurricane Florence has already proven to be not just powerful and destructive but wildly unpredictable.
After appearing headed toward the North Carolina-Virginia border at one point, Florence shifted south and is now taking aim at the Carolinas. And while the intensity of Florence's winds still in the 90 mph range have diminished enough to turn it into a Category 1, the storm has grown in size as it crawls off the coast at a plodding 6 mph.
So, what can we tell for certain about what the National Weather Service has called the "storm of a lifetime''? We know it has forced the cancellation of nearly 1,800 flights, with more to come, and that it has already caused serious flooding in coastal areas.
Here are answers to other critical questions:
Where is Florence now?
As of 11 p.m. EST, Florence was about 50 miles south of Morehead City, North Carolina, and 60 miles southeast of Wilmington, North Carolina, according to the National Hurricane Center.
It had sustained winds of 90 mph and was moving in a northwest direction. Wilmington is expected to get battered before the storm drifts south.
What's the biggest concern?
Definitely the storm surge, which could be up to 11 feet in some locations. That's high enough to cover a house not on stilts. The hurricane center described the storm surge as "life-threatening.''
"The deepest water will occur along the immediate coast in areas of onshore winds, where the surge will be accompanied by large and destructive waves,'' it said. "Surge-related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances.''
Does it matter that Florence is moving slowly?
Yes, because it's bringing a voluminous amount of rain, and by lingering it creates worse flooding. The Outer Banks of North Carolina took the initial brunt Thursday afternoon, with parts of Highway 12 the main road that runs through Ocracoke and Hatteras islands flooding and becoming impassable.
Southeastern coastal North Carolina and far northeastern South Carolina are expected to get pelted with 20 to 30 inches of rain, and some isolated spots may get up to 40 inches in 48 hours.
Why is it getting bigger?
By hovering over the warm water in the Atlantic Ocean, the storm is being nourished. Hurricanes feed off the heat in the warm surface of the ocean and typically lose power when they hit land.
Some predictions are calling for Florence to dump as much as 10 trillion gallons of rain on the region. That's about half the amount Hurricane Harvey the largest rainfall event in U.S. history dropped on the greater Houston area last year.
When will it make landfall?
Forecasts call for the eye to hit land sometime Friday near the Carolinas border. While inland areas may be spared the strongest winds, they could be vulnerable to flooding, especially if close to overflowing rivers.
The hurricane center said the large amount of rainfall "will produce catastrophic flash flooding and prolonged significant river flooding.''
How many people are without power?
As of 9 p.m. EST, North Carolina Emergency Management reported that 102,308 customers were without power even before Florence made landfall.