Experts at the U.S. National Hurricane Center in Miami have expanded a warning as tropical storm Ernesto approaches Florida. A tropical storm warning now extends from the Florida Keys, an island chain extending from southern Florida, to the east coast of the southern U.S. state of Georgia.

The center warned Tuesday that Ernesto could intensify into a hurricane and that isolated tornadoes are possible in the keys and southern Florida.

Heavy gusts of wind, drenching rain and storm surge flooding of up to one meter is expected in the area. Florida Governor Jeb Bush has declared a state of emergency and advised residents to make sure they have enough food and water to last for three days.

Earlier Tuesday, NASA started moving the space shuttle Atlantis back into its hanger after weather forecasts placed the storm within 32 kilometers of the Cape Canaveral launch pad in the southern U.S. state of Florida.

The storm poured up to 25 centimeters of rain on Cuba Monday. Thousands of Cubans evacuated to higher ground on Sunday before the storm made landfall. There have been no reports of deaths or serious damage.

In Haiti, the storm's death toll has risen to two people.

Some information for this report was provided by AP.