The FCC official said the agency is still investigating those outages.
Following some disasters, the FCC has used a device that analyzes which frequencies are still carrying signals, and which frequencies have gone dark. The official said it is unclear whether the FCC will have to use the device in the aftermath of Isaac.
Last month, the FCC began exploring the possibility of launching flying cellular transmitters after disasters to restore service.
The transmitters could be attached to unmanned drones or balloons and would take the place of disabled cell towers.
The FCC's notice of inquiry asked for comments on the costs and benefits of the project, which wireless frequencies the transmitters should use and how to coordinate with other government agencies.
The FCC is still exploring the possibility of the technology, but it might not be available any time soon.