The Florida Keys were placed under a hurricane watch Friday night, and Tropical Storm Isaac was getting better organized as it moved northwest toward Haiti, the National Hurricane Center in Miami said.
The storm strengthened somewhat and sped up in the hours before the hurricane center's latest update at 11 p.m. As of that time, the storm had maximum sustained winds of 70 mph as it moved northwest at 14 mph about 65 miles south-southwest of Port-au-Prince and about 245 miles southeast of Guantanamo, Cuba.
Rainfall of 8 to 12 inches, with maximum totals of 20 inches in some places, were possible over the island of Hispaniola, according to the National Hurricane Center.
The latest NHC track showed Isaac remaining a tropical storm as it approached the Florida Keys Sunday.
The Keys will have tropical force winds starting Sunday morning and Isaac will make landfall Sunday night, Gov. Rick Scott said in a Friday afternoon briefing. He said there have been no evacuations yet in the state.
“The concern is that the more time it spends over warm water, the greater chance it’s going to be a big storm," he said.
But, he said, “Hopefully we’ll get lucky here and it will dissipate over Cuba."
A hurricane watch was in effect for Haiti, the Florida Keys including the Dry Tortugas, Florida Bay, the east coast of Florida south of Ocean Reef, and the west coast of the state south of Bonita Beach.
A tropical storm warning was also in effect for the Keys including the Dry Tortugas, Florida Bay, the east coast of Florida south of Ocean Reef, the west coast of the state south of Bonita Beach, and Lake Okeechobee.
NHC Director Dr. Rick Knabb and Congresswoman Debbie Wasserman Schultz said residents throughout the state need to be prepared. They both said that although Florida has been mostly spared from major damage in recent years, it doesn't mean residents should be any less vigilant.
"There is a risk that many of us have become somewhat complacent," Wasserman Schultz said. "I urge folks to take a moment to review your checklists for supplies and be sure, as Dr. Knabb said, that your family has a plan in case of an emergency."
"The luck is gonna run out at some point. Now we don't know exactly what Isaac is going to do to particular parts of Florida but this is very much a strong reminder, especially for folks who have never been through this, that the threat is real," Knabb said. "Tropical storm and hurricane threats to Florida are real."
Robert Molleda, warning coordination meterologist with the National Weather Service in Miami, said the worst of the weather would possibly hit South Florida as early as Sunday morning and last into Monday.
"On this current track, we would escape impact but we would have the strongest winds," he said.
Although the track has been gradually shifting to the west, South Florida would be on the northeast side, and it would still be impacted with nasty weather including 40 mph winds, heavy rains and tornadoes. Flooding would is also a possibility, he said.
"The northeast side is normally the sector of the storm ... that would be where tornadoes would most likely occur," he said.
Officials in Monroe County have already cancelled school for Monday, and Emergency Management Director Irene Toner anticipated declaring a local state of emergency on Friday.
Emergency shelters will open at 2 p.m. Saturday in Monroe County. Shelters open are at Key West High School, Stanley Switlik Elementary School in Marathon and Coral Shores High School. County offices, sheriff's offices and county courts will also be closed on Monday.
"We're monitoring the storm very closely and we'll probably make a decision this afternoon about evacuating the tourists but it's looking better and better that we don't have to with the storm not forecast to be a hurricane by the time it gets here," Key West Mayor Craig Cates said Friday. "If we evacuate the tourists it costs us millions of dollars."
At a news conference Friday, Miami-Dade Mayor Carlos Gimenez said he doesn't anticipate any evacuations but they're moving forward with emergency operations planning.
Meanwhile, organizers of next week's Republican National Convention in Tampa continued to monitor the storm, though Scott didn't anticipate it would be cancelled.
“We’re still committed to having a great convention. And one thing you can feel great about this state is we’re prepared," he said.
Scott said the state was ready for the storm and that officials had no indication that people were cancelling their trips south. "This is a state that understands hurricanes, we know how to prepare for them," he said.
He asked residents to get prepared and to have three days of food and water on hand.
The center of Isaac was expected to make landfall in Haiti overnight and move near or over southeastern Cuba on Saturday, the NHC said. The storm was expected to weaken somewhat as its center crosses Haiti and southeastern Cuba, and keep moving toward the northwest.
Tropical storm force winds extend outward up to 230 miles from the center of Isaac.
A tropical storm warning was in effect for the Dominican Republic, Haiti, the Cuban provinces of Ciego De Avila, Sancti Spiritus, Villa Clara, Camaguey, Las Tunas, Granma, Holguin, Santiago De Cuba and Guantanamo, the Bahamas, and the Turks and Caicos Islands.
A tropical storm watch was in effect for Jamaica, the Cuban provinces of Matanzas and Cienfuegos, the Cayman Islands, and Florida's east coast north of Jupiter Inlet to Sebastian Inlet.
Out in the Atlantic, Tropical Depression Joyce remained weak with maximum sustained winds near 35 mph. Joyce wasn't expected to strengthen over the next 48 hours and there were no threats to land.