Rita, weakening but still a dangerous Category 3 hurricane, is closing in on the Texas-Louisiana border, a region packed with major refineries.
The National Hurricane Center downgraded Rita to a strong Category 3 storm packing 125 mph winds but despite weakening, meteorologists warn Rita is still capable of causing extensive damage.
Rita's eye is 175 miles southeast of Port Arthur, Texas, moving northwest on a path that looks likely to take it over Port Arthur and Lake Sabine on the Texas-Louisiana border.
Rita is pushing an 18-foot storm surge toward the coast, spilling over levees and flooding parts of New Orleans inundated just over three weeks ago by Katrina.
Texas officials estimated Rita has sent at least 2.5 million people scurrying for high ground, the biggest evacuation in the state's history.
Galveston, right on the Gulf of Mexico, is already empty.
In Houston, with major highways hopelessly gridlocked and the fury of the storm just hours away, residents still stuck in this city of 2 million were advised to ride out the storm as best they can at home.
Houston's two airports are now shut.
A bus carrying elderly evacuees from Houston caught fire early Friday, killing perhaps as many as 20 and adding carnage to the chaos on the road to Dallas, a road already littered with stranded motorists unable to find gas.
Rita is moving at 10 mph and will hit land in a matter of hours.
