It is expected to migrate from Florida to the north and then from the US mainland, the NHC said.
"Even if you only speak 2 to 4 inches (of rain), you have to remember many of these houses, they have no roofs, many of the buildings are already structurally affected, leaving even a wind of 80 or 90 km / h can do more damage, "said CNN meteorologist Allison Chinchar.
The islands got some rain, Van Dam said, but Humberto's full effect was not achieved.
"They were spared the heaviest rainfall and strongest winds centered north and east of the storm," said Van Dam, adding that the storm surge in the Bahamas was negligible.
Many in the Bahamas are still out of the house after the devastating Hurricane Dorian, which was hit by the islands about two weeks ago.
The figure includes US citizens, rightful residents, the Bahamas, and people from other countries who evacuated the islands after the storm.
Palm Beach County, Florida, has begun registering expelled students who have fled Dorian's harm. School-worn backpacks will be provided to students from the Palm Beach County Education Foundation, which plans to open their school supplies business to allow evacuated families to shop for free, said district spokeswoman Julie Houston, Christina Maxouris and Jason Hanna contributed to this report.