Meteorologists say Hurricane Rita is gaining strength rapidly as it moves west through the Florida Straits, between Havana, Cuba, and the Florida Keys.
The U.S. National Hurricane Center says Rita's maximum sustained winds have increased to 160 kilometers per hour. Rita is now a category-two hurricane after being upgraded to a category-one storm earlier Tuesday.
High winds and heavy rain are lashing southern Florida and the Keys, a low-lying chain of islands off Florida's southern coast.
Hurricane warnings remain in effect there and in parts of western Cuba. Thousands of tourists and residents fled the Keys ahead of the storm, acting on warnings from state and local officials.
Forecasters expect Rita to enter the Gulf of Mexico by Wednesday, and say it is possible that Rita will strike areas along the U.S. Gulf Coast devastated three weeks ago by Hurricane Katrina.
As a precaution, officials in Galveston, Texas have urged residents to evacuate.
Some information for this story provided by AP and Reuters.