Forecasters said conditions will only get more lethal as the storm smashes ashore early Friday near the North Carolina-South Carolina line and crawls slowly inland.
The decision came hours after revised forecasts showed the potential for a greater impact on SC from the hurricane, so the game's cancellation will free up hotel rooms in the Columbia area for evacuees while allowing emergency personnel to be utilized in areas impacted by the storm.
As of 8 p.m., the storm was centered 335 miles (540 kilometers) southeast of Wilmington, North Carolina, moving northwest at 16 mph (26 kph).
Although slow weakening is expected to begin by late Thursday, Florence is still forecast to be an extremely risky major hurricane when it nears the US coast late Thursday and Friday.
Trump says his administration has been in "close contact" with the state and local governments soon to be impacted by the massive storm.
Its maximum sustained winds slackened slightly to 125 mph, qualifying it as a Category 3 storm, but its wind field has grown, with hurricane-force winds extending out 70 miles from the center and tropical storm-force winds stretching as far as 175 miles from the storm's center. Favorable wind patterns. Higher sea levels that exacerbate storm surge.
SC athletics director Ray Tanner said that consideration for those in the Palmetto State who will likely be hit hard by Florence led to canceling the game.
"This is not going to be a glancing blow", said Jeff Byard, an administrator with the Federal Emergency Management Agency.
We started the day in Raleigh, North Carolina, where we met Gov. Roy Cooper at the state's emergency operations center.
Forecasters said that given the storm's size and sluggish track, it could cause epic damage akin to what the Houston area saw during Hurricane Harvey just over a year ago, with floodwaters swamping homes and businesses and washing over industrial waste sites and hog-manure ponds.
Computer simulations - especially the often star-performing European model - push the storm further south, even into SC and Georgia.
When Hurricane Matthew made landfall in 2014, Benson and her family stayed because it was only a Category 1 storm.
"In fact, this entire area is under a mandatory evacuation order", he said. "Disaster is at the doorstep and is coming in", he said in a tweet.
Melody Rawson evacuated her first-floor apartment in Myrtle Beach and arrived at Atlanta Motor Speedway in Hampton, Georgia, to camp for free with three other adults, her disabled son, two dogs and a pet bird. Workers are being brought in from the Midwest and Florida to help in the storm's aftermath, it said.
"I feel just as safe at home as I would at a shelter", Batts said.