Isaac will spend this weekend crossing Cuba before threatening Florida and the central Gulf Coast in the upcoming days.
According to Dan Kottlowski, head of the AccuWeather.com Hurricane Center, "Given Isaac's current position and momentum in the Caribbean, the storm is much more likely to track into the Gulf of Mexico than to track along the east coast of Florida."
Those Gulf Coast communities that lie from eastern Louisiana to the Florida Panhandle are now at greatest risk of becoming Isaac's eventual target around Tuesday night of next week.
Before that, the Florida Peninsula still faces significant hazards.
Beginning as soon as later Sunday, outer rain bands will start sweeping across the Florida Keys as Isaac approaches. Heavier rain and tropical storm-force winds will follow for the Keys and all of South Florida, including Naples and Miami, Sunday night into Monday.
A larger version of the latest forecast track map for Isaac (with times in EDT) can be found on the AccuWeather Hurricane Center.
Squally showers and thunderstorms will continue to spread northward across the Florida Peninsula through Tuesday as Isaac makes its northward trek through the Gulf of Mexico. Such squalls will contain flooding rain, tropical storm-force wind gusts and isolated tornadoes.
Both coastlines of Florida could face beach erosion and coastal flooding. The southeastern coast (home to Miami) will be faced with the danger as Isaac approaches, while the western coast will be threatened after Isaac passes by to the north.
As Isaac approaches, winds circulating around the storm will drive ocean water onto the southeastern coast as offshore winds do the opposite along the southwestern coast.
"As the system moves up over the eastern Gulf, a return flow from the west and southwest in the wake of the storm can bring a storm surge along the Florida west coast," stated AccuWeather.com Expert Senior Meteorologist Alex Sosnowski.
Isaac's strength and proximity to Florida's western coast will determine the severity of the storm surge.
The above impacts are based on the AccuWeather.com Hurricane Center's forecast that brings Isaac through the Florida Keys early Monday morning.
There is concern that Isaac will eventually track a bit more to the east, passing over mainland Florida's southern tip and the southwestern coast.
Such a track would put more of South Florida at risk for Isaac's strongest winds with the heaviest rain spreading farther northward into central Florida.
With Isaac's exact track not set in stone, all residents through Florida and the Gulf Coast should closely monitor its progress.
Isaac is currently a strengthening tropical storm in the Caribbean. While some weakening will take place over Cuba, the door will open for rapid intensification once Isaac enters the Gulf of Mexico.
Isaac could quickly strengthen into a Category 2 hurricane prior to its final landfall. There is even growing concern that Isaac will continue intensifying into a major hurricane (Category 3 strength or higher); the longer Isaac spends over water, the more valid this concern becomes.
When Isaac finally reaches the central Gulf Coast or Florida Panhandle, the future powerful hurricane will come onshore with destructive winds, widespread flooding rain, tornadoes and coastal flooding.
The dangers of Isaac will not end when the storm makes its final landfall. Flooding rain and isolated tornadoes will continue to accompany Isaac inland through the South.
The weather threatens to interfere with search, rescue and cleanup operations in the wake of the major 7.8-magnitude earthquake that has killed more than 1,000 people with the death toll mounting.
Severe thunderstorms that developed over the South Central states on Friday afternoon have continued throughout the night and are now threatening the central Gulf Coast.
Rain could cause a rain delay, or even the postponement of Saturday night's NASCAR race with the green flag set to fly at 7 p.m. EDT at Richmond International Raceway.
A strong thunderstorm crossed Sydney, Australia, on Saturday, covering the ground with hail.
The 7.8-magnitude temblor hit at 11:56 a.m. local time Saturday with an epicenter 81 km (50 miles) northwest of Kathmandu, Nepal, the nation's capital, the United States Geological Survey reported. It was at a depth of 15 km (9.3 miles).
Residents of Boston will want to keep their umbrellas handy through Monday.
Fairbanks, AK (1991)
Still two feet of snow covering the ground.
Fort Wayne, IN (1996)
58 mph wind gust.
Amarillo, TX (1997)
6.4" of snow.