A large portion of Florida’s western and Panhandle coast was already under a tropical storm warning when the National Hurricane Center announced that a swift-moving depression had become a named storm. The centre said it is the earliest that a third named storm has ever formed in the Atlantic basin.
Colin’s maximum sustained winds yesterday had increased to nearly 80kph, with slow strengthening possible.
The storm was centred about 450km west-southwest of Tampa and moving north-northeast at nearly 25kph.
The latest forecast for Colin called for the storm to make landfall near the Big Bend area of Florida in the mid-afternoon, move across the Florida peninsula into Georgia, and then move along or just off the South Carolina coast before heading out to sea.
Schools in at least one Florida Gulf Coast county planned to dismiss students early.
Forecasters said up to 20cm of rainfall is possible across western Florida, eastern Georgia, and coastal areas of the Carolinas today.
Meanwhile, Mr Scott postponed a meeting last night with presumptive Republican presidential nominee Donald Trump in New York so he can remain in the state capital.
Mr Scott warned residents not to simply look at the centre of the storm, saying the heaviest rain will be to the east and west of it.
Colin was expected to pass the Georgia coast before dawn today, with flash floods posing the greatest threat.