Hurricane Irma, now 400 miles wide, continued its march of devastation on Monday morning, dumping rain across the width of Florida and lashing the state with powerful winds that downed power lines and left millions in the dark.
As the storm moved inland, it was downgraded to Category 1. Losing some of its deadly power but retaining its vast size, the storm stretched from Florida’s West Coast to the Atlantic as it churned its way from the Florida Keys toward Tampa.
The hurricane came ashore on the mainland as a Category 2 storm, flooded parts of downtown Miami and knocked over construction cranes there as winds exceeded 100 m.p.h.
Here’s the latest:
• The storm’s eye was near Tampa at 3 a.m. Forecasters expect it to stay inland over Florida as it heads into Georgia, before moving on to Alabama and Tennessee.
• At least four people in Florida have been killed by the storm. It has left at least 27 people dead across the Caribbean.
• More than 3.3 million customers are without power across Florida. The full extent of the damage is not yet known.
Retreating water alarms observers.
Suddenly, the water went away. In the Bahamas, in Tampa Bay and in Naples, observers were shocked to see the waters that usually lap against the shore recede into the distance.
On social media, people reacted with incredulity, noting that the water had disappeared where whitecaps were just hours before on Sunday in Tampa Bay. James Spann, an Alabama meteorologist and weather blogger, reacted sternly to a photograph on Twitter of people playing in the sand exposed by the retreating water.
“The water will come rushing back with a vengeance,” Mr. Spann said on Twitter. “They won’t have time to get out when it begins.”
On Twitter, Gov. Rick Scott issued an urgent warning to stay away from the water. “DO NOT GO IN. The water will surge back & could overtake you.”
Chris O’Donnell, a reporter with The Tampa Bay Times, later reported that the police had cleared people off of the shore well before the water came back.
The phenomenon of water being drawn off by the power of Hurricane Irma is known as a negative surge. As Mr. Spann warned, that odd condition will not last — and will become dangerous. Michael R. Lowry, a scientist with the University Corporation for Atmospheric Research, a nonprofit education consortium, explained in a series of tweets that…