Hurricane Rita now category 5

MIAMI, Sept. 21 (UPI) -- Hurricane Rita has become the third-most intense hurricane on record in the Atlantic Basin, with top sustained winds near 165 mph over the Gulf of Mexico.

Forecasters upgraded Rita to a potentially catastrophic category 5 storm Wednesday. At 8 p.m. EDT, the National Hurricane Center said the center of the storm was about 580 miles east-southeast of Galveston, Texas, moving toward the west at almost 13 mph.

A hurricane watch was posted for the Gulf of Mexico coast from Port Mansfield, Texas, to Cameron, La. A tropical storm watch was posted for east of Cameron to Grand Isle, La., and from south of Port Mansfield to Brownsville, Texas.

The government of Mexico issued a tropical storm watch for the northeast cost of Mexico from Rio San Fernando northward.

The storm was not expected to make landfall before Saturday morning, and it is not clear yet where it will hit. For now, Rita is on a course that could threaten Houston, and Texas Gov. Rick Perry declared the state a disaster area Tuesday night.

Houston Mayor Bill White urged residents Wednesday to prepare.

"People in the storm surge areas ... are encouraged to evacuate and make their evacuations plans," he said.

President Bush Wednesday declared a state of emergency in Texas and Louisiana.