The US National Hurricane Center said the center of the storm, packing maximum sustained winds of 50 miles (80 kilometers) per hour, was passing about 30 miles to the east of Great Abaco Island, one of the areas hardest hit by Dorian.
In the morning, the storm was "nearly stationary," US meteorologists said.
About two to four inches (five to 10 centimeters) of rain were expected in most areas, with isolated flooding in low-lying areas, the Bahamian National Emergency Management Agency (NEMA) cautioned.
"Significant storm surge is not expected in the northwestern Bahamas from this system," the Miami-based NHC said, however -- good news for residents of Abaco and Grand Bahama still trying to get back on track after Dorian swept through early this month.
"I know this is not something people in Abaco and Grand Bahama would like to hear at this time, but it's out there and the storm will bring heavy downpours over the Bahama islands," Shavon Bonimy, senior meteorologist in Grand Bahama, told The Nassau Guardian.
"So we have to be prepared."
NEMA spokesman Carl Smith told reporters on Friday that the storm would likely "slow down logistics" of relief efforts, but added: "We have contingency plans in place."
"Fuel and water remain the biggest needs in Abaco," Smith said.
So far, the death toll from monster storm Dorian is at 52, but officials say that number is likely to go up. About 1,300 people are still unaccounted for, but Smith said officials are working to cross-reference new data and locate the missing.
Former Bahamian prime minister Hubert Ingraham said earlier this week he feared the final death toll could be in the hundreds.
Humberto is expected to strengthen into a hurricane late Sunday, the NHC said, but by then it will be clear of the Bahamas and well off the coast of Florida, and it is not expected to have a major impact on the US.
"The chance of heavy rainfall affecting the southeastern United States has diminished," the NHC said.
UN Secretary-General Antonio Guterres, who has been visiting the Bahamas, said Dorian demonstrated the need to address climate change.
"In our new era of climate crisis, hurricanes and storms are turbo-charged," Guterres said.
"Science is telling us: this is just the start. Without urgent action, climate disruption is only going to get worse. Every week brings news of climate-related devastation."
On Saturday, Guterres tweeted about his visit the day before to the Bahamian government's emergency storm operations center, congratulating officials for their "leadership responding to this tragedy."
"The United Nations stands with the Bahamas and the Caribbean," he said in remarks to workers at the center.
Smith said 71 people were staying in shelters on Grand Bahama island and 2,037 in shelters in New Providence, where Nassau is located.