(CNN) -- A huge plume of black smoke soared above the picturesque Georgia city of Savannah on Saturday afternoon, prompting officials to urge people to stay inside to avoid the fumes.
The fire began around 11:30 a.m. inside a warehouse located in the Georgia Port Authority's Ocean Terminal, just west off of the city's historic riverfront, said Savannah Fire Department spokesman Mark Keller.
The warehouse contains pallets of solid rubber that were burning, according to Keller.
Crews had contained the blaze to within half the building within a few hours, the fire spokesman said. Firefighters planned to remain on-site overnight.
There were no reported injuries or evacuations.
If the sight of the large column of rising black smoke wasn't enough, people were being told not to go outside.
"If you don't have to go out, we advise to stay inside," Keller said Saturday.
The National Weather Service issued a dense smoke advisory through 6 a.m. Sunday for much of Georgia's Chatham County, including parts of the Savannah metropolitan area. This is an extension of a previous advisory that was supposed to end at 11 p.m.
Visibility was expected to be at its worst through 4 a.m. or 5 a.m., and problems could become exacerbated when fog mixes in with the smoke.
"Everyone is encouraged to stay indoors as the air quality will be hazardous. Avoid strenuous activities if you must work outdoors," the advisory warned. "Motorists should be alert for sudden changes in visibilities."
The Savannah College of Art and Design tweeted that people should avoid the River Street area, a popular spot for tourists filled with restaurants and stores.
Kayvon Gerami, a CNN iReporter, said that people stopped along the Talmadge Memorial Bridge to photograph the fire.
"The black smoke started to look like a tornado," the 28-year-old Gerami said. "And now it smells like burnt tires everywhere."
Firefighters got some help from the weather. Winds were calm, according to the National Weather Service.
"Pretty much (the smoke) is going straight up," said Vern Beaver, a National Weather Service meteorologist in nearby Charleston, South Carolina. "It doesn't seem to, right now, be producing much of a restriction to visibility."
Winds out of the north-northeast were expected to pick up and be about 8 mph, Beaver added. If they do, they'd push whatever smoke is left offshore over the Atlantic Ocean.
Authorities haven't yet determined what caused the fire. Keller said it won't be until Sunday or later when investigators can get into what's left of the charred warehouse.
CNN's Jareen Imam, Margaret Blaha and Phil Gast contributed to this report.