KEY WEST, Fla. (AP) – A hurricane watch was issued Sunday for the Florida Keys and Gov. Jeb Bush ordered a state of emergency in anticipation of Tropical Storm Ernesto. Ernesto, which had strengthened into a hurricane for about 10 hours, weakened back into a tropical storm by late afternoon with top sustained winds of 60 mph, the National Hurricane Center said.

Still, the Miami-based hurricane center said the storm was expected to strengthen and potentially reclaim its hurricane status before reaching the southeastern coast of Cuba on Monday morning.

“It certainly looks like it’s going to impact a significant portion of Florida before it’s all over,” said Max Mayfield, the director of the National Hurricane Center.

Officials in the Keys told tourists to postpone any immediate plans to travel there and ordered those already in the island chain to leave. All travel trailers and recreational vehicles were ordered off the islands immediately. Residents were taking notice too: a Home Depot store in Key West was busy Sunday as customers shopped for generators and other storm-preparation equipment.

The state of emergency directs counties to open their emergency management offices and activates the National Guard, among other things. Bush canceled his scheduled trip to New York for several meetings Monday, choosing instead to stay in Tallahassee and monitor storm developments.

Ernesto, the first hurricane of the Atlantic season, lashed Haiti and the Dominican Republic on Sunday with heavy rain, prompting fears of mudslides and flooding. The storm was expected to arrive in southern Florida by early Tuesday, the National Hurricane Center said.

Tourists including Jim Rogers, of Lodi, N.J., made preparations Sunday to leave the low-lying Keys, which are connected to each other by just one highway, U.S. 1. Traffic leaving the Keys on the single evacuation route was steady but not heavy Sunday afternoon.

Rogers was part of a group of eight visiting Key Largo and had planned to stay in the Keys until Thursday or Friday. Rogers said the group now might go to Naples, but they were not going home.

“You don’t know where to go. You don’t know where it’s going to blow,” he said. “You don’t want to be in Key West.”

Key West International Airport was expected to remain open until at least Monday night. Local authorities will begin moving special needs patients to a shelter Monday morning, and nine state parks in the county were closed Sunday “until further notice” in anticipation of the storm.

The hurricane center urged residents of southern Florida, the Florida Keys and Mexico’s Yucatan Peninsula to monitor the storm. It was projected to strengthen off western Florida on Wednesday but the location of any U.S. landfall was unclear.

“It’s on a track toward the Florida peninsula early this week and all of Florida is in the area that’s being threatened, from the Keys all the way up to the Panhandle,” said Michael Brennan, a meteorologist at the center in Miami.

Florida has been hit by eight hurricanes in the past two years.

“The message to Floridians is that Ernesto bears watching,” said Mike Stone, spokesman for the Florida Division of Emergency Management.