Ivan's stormy trek floods Southeast
Hurricane gives rise to tornadoes; at least eight killed
Gulf Shores, Alabama experienced significant flooding.
A Pensacola hospital was damaged by the storm.
Hurricane Ivan slams Blountstown, Florida
MOBILE, Alabama (CNN) -- Remnants of Hurricane Ivan soaked the Southeast Thursday evening after the storm came ashore with full force in Alabama and spawned tornadoes that killed eight people.
Florida Gov. Jeb Bush called the storm "devastating" and said his heart went out to the families of those who died and to all residents on the Gulf Coast whose homes were damaged.
Downgraded to a tropical storm, Ivan left more than 1.1 million people without power in Florida, Alabama and Mississippi. (State-by-state impact)
The insurance forecasting firm Eqecat estimated Ivan caused between $4 billion and $10 billion in damage and that 30 percent to 50 percent of Ivan's insured losses occurred in and around Pensacola.
President Bush declared Florida, Alabama, Louisiana and Mississippi disaster areas, making federal funding and aid available. The declaration for Florida was the third in a month, following those issued for hurricanes Charley and Frances.
More than 2,000 National Guard troops were moving into northwest Florida to assist with assessment and cleanup operations, Gov. Bush said.
"Entire houses were taken off their foundations and disappeared because of the storm surge on the barrier islands," Gov. Bush said. "These are newly built luxury homes that don't exist right now. That's pretty powerful."
In Pensacola, winds sheared off the exterior of a section of West Florida Hospital, said a spokeswoman, but patient wings were undamaged. Three other hospitals in the area also were damaged, officials reported.
Storm damage made travel from Pensacola difficult. Highway 90 was closed, as was Interstate 10 over Escambia Bay, where an 18-wheel truck plunged into the water and trapped the driver in the rig.
Winds throughout the west Florida area bent billboard signs, damaged trees, ripped roofs off buildings and scattered debris.
"As I have said before, man gets put in his place when he understands that at a particular point in time when it comes to nature, all he is is an observer," said Panama City Beach Mayor Lee Sullivan.
Damage was heavy in other spots as well. Downed trees and power lines were reported all along the coast.
In Biloxi, Mississippi, a few restaurants and a church lost parts of their roofs, and in Jackson County, along the Alabama state line, some gas station awnings -- and even the pumps themselves -- were blown over.
As of 11 p.m. ET, the National Hurricane Center in Miami said the storm was centered 25 miles (40 kilometers) north-northwest of Gadsen, Alabama, and headed north-northeast at about 14 mph (55 kph) with sustained winds around 35 mph (97 kph) and higher gusts.
The hurricane center said rainfall amounts of 8 to 12 inches were possible through Saturday in the Southeast.
Storm-related tornadoes in the Florida Panhandle ahead of Ivan's landfall killed at least two people Wednesday in the resort town of Panama City Beach.
Early Thursday, a powerful tornado leveled homes in Blountstown, west of Tallahassee, killing four people.
A young girl in Milton died when a tree fell on her house, said a spokesman for Santa Rosa County.
One person southwest Georgia died when a tree fell on a car Thursday afternoon, possibly the result of a tornado, a Franklin County official said.
Ivan made landfall on the east side of Mobile Bay in Alabama at 1:50 a.m. (2:50 a.m. ET) Thursday as a slightly weakened Category 3 hurricane with winds of 130 mph (208 kph).
The mayor of Mobile breathed a sigh of relief and said it appeared damage to his city was less extensive than feared. "I think we caught a bullet with our teeth," said Mayor Michael Dow.
It was a different story in nearby Gulf Shores, Alabama, where water as high as 6 feet covered much of the barrier island.
An emergency services representative from Baldwin County, Alabama, toured the Gulf Shores area and expressed dismay.
"Orange Beach [east of Gulf Shores] all the way down to what was the FloraBama, it is no longer there. I just can't express the devastation that's there. Just every single condo or hotel, rental unit, had some extensive damage," she told reporters.
Authorities in Gulf Shores were looking for at least 13 deer and six alligators that were not evacuated from a local zoo and were seen wading and swimming through the floodwaters.
One of the alligators on the loose is named Chuckie, which measures 12 feet long and weighs 1,000 pounds, authorities said.
Another alligator was shot and killed, but authorities said they planned to only tranquilize the deer they manage to find.
Oil companies were assessing damage after hundreds of oil rigs were evacuated in the Gulf of Mexico.
Transocean Inc. reported an oil rig missing, but the Deepwater Nautilus was later found 73 miles northeast of its original location. Diamond Offshore Drilling also reported a rig afloat, but it was located and the company reported no apparent damage or pollution.
A spokesman for the Minerals Management Service said it was not unusual for drilling rigs to break free during a storm of Ivan's intensity.
But spokesman Curtis Carey said the potential danger is from damaged pipelines since the rigs' anchors drag on the gulf floor. He said there have been no reports of damage to pipelines so far.
The Gulf of Mexico is home to about 25 percent of U.S. oil and gas production and there was concern about sustained disruptions to the flow of oil and gas.
Oil companies evacuated 545 offshore rigs as the storm approached, disrupting 83 percent of daily production -- about 1.7 million barrels of oil a day, the service said.
In addition, more than half of natural gas production was disrupted, the service reported.
Tropical Storm Jeanne
Hurricane Jeanne lost some of its strength Thursday, after it scraped the northern coast of the Dominican Republic and appeared headed for the Bahamas.
Jeanne had sustained winds of 70 mph (110 kph), the National Hurricane Center in Miami said.
As of 11 p.m., Jeanne's center was 65 miles (100 kilometers) northeast of Santo Domingo in the Dominican Republic and was moving west-northwest at 6 mph (9 kph). (Full story)
CNN's Kathleen Koch and Susan Candiotti in Biloxi, Mississippi, Rick Sanchez in Panama City Beach, Florida, Gary Tuchman in Gulf Shores, Alabama, and Sara Dorsey in Pensacola, Florida, contributed to this report.