Washington: Already key metrics are being measured in the millions - millions evacuated from their homes, millions without power and millions effectively twiddling their thumbs as daily life has ground to a halt.
And tens of millions in the rest of the country glued to TVs, watching it all.
Miami seemingly dodged a bullet, but Florida's densely populated and ill-prepared Tampa region came into the cross hairs as Hurricane Irma barrelled up the west coast of the southern state through Sunday US time.
After a week of it messing with Caribbean island communities, Irma made landfall with the Florida peninsula at Cudjoe Key, one of dozens of low-lying islands at the southern tip of the state.
Upgraded to Category 4, after a day at sea as a relatively less harmful Category 3, Irma is so wide that the entire state of Florida is affected.
But through Sunday, the focus narrowed to the peninsula's western flank - particularly St Petersburg - with warnings that even if destructive winds didn't cripple communities, rising water associated with catastrophic storm surges and torrential rain could be just as destructive.
Still offshore, and tracking the coast on a more westerly line than experts had predicted, Irma's precise intentions remained something of a puzzle.
Michael Brennan, a senior hurricane specialist at the National Hurricane Center, told reporters early on Sunday: "It could make landfall anywhere along the west coast. It's really hard to predict where the eye will make landfall on the west coast once it leaves the Keys."
"Anywhere" became the coastal community of Marco Island, where wind gusts of about 210 km/h were recorded at 3.35pm. But despite that, it seemed that Irma had lost a bit of her punch, because she was ratcheted back to Category 3.
On Sunday morning, William "Brock" Long, administrator of the Federal Emergency Management Agency, told ABC's This Week: "It's going to skirt the west coast and drive storm surges not only from the Keys but well up the coast of Florida. So, it's a worst-case scenario for Florida on the west coast."
But as Irma dawdles northwards, at about 12 km/h or 15 km/h, emergency response experts fretted that the sprawling Tampa region, likely to be hit in the early hours of Monday, local time, was a worrisome target because it's infrastructure providers had not reckoned on the lethal likes of Irma arriving in their midst.
And in that, there is double jeopardy - because Tampa is so far north and so removed from the anticipated danger zone, many of the millions evacuated from the east of the state in recent days had made their way to Tampa.
Tampa fell in with nearby communities - it imposed a curfew to take effect at 6pm Sunday - and Mayor Bob Buckhorn fell back on the philosopher-pugilist Mike Tyson to convey his message on the extent to which Tampa might be winging it - "Everybody has a plan until they get punched in the face - well, we're about to get punched in the face."
As early as Sunday morning, about two million homes and businesses were without power - and the Florida Power and Light company issued a warning that thieves were masquerading as utility staff to gain access to homes, which they were robbing.
More than seven million people, almost one-third of the state population, were covered by evacuation orders - mostly in Florida, but also in Georgia and South Carolina. And coastal counties, like Collier and Lee, reported difficulty in finding shelter space for a last surge thousands who had decided to abandon their homes.
And three deaths were being attributed to the hurricane - all in traffic accidents.
Across the state, 29 hospitals, 239 assisted-living centres and 56 other health care facilities in the state had been evacuated and more than 60 of hundreds of emergency shelters were geared to people with special needs.
The islands of the Florida Keys were forecasted to get as much as 63 cm of rain. And though the hurricane had moved northward through the afternoon virtually no detail was being reported on damage - or a lack there of - from the keys.
Governor Rick Scott told a TV interviewer: "We don't have the exact numbers on everyone who stayed in the Key - I hope everyone listened [to official warnings that they evacuate]."
Though Miami seemed to have been spared destructive winds, many roads were becoming impassable through Sunday as floodwaters rose.
Wind gusts were recorded at 110 km/h to 150 km/h about midday on Sunday - and were expected to continue for the rest of the day, sufficient to bring down power lines, uproot trees and leave at least one tower crane on the city skyline dangling precariously.
The story For Hurricane Irma, the metrics are measured in millions first appeared on The Sydney Morning Herald.