Tyndall Air Force Base in Panama City suffered "widespread catastrophic damage" and will require "extensive cleanup and repairs", said base leaders.
Col. Brian Laidlaw told the 3,600 airmen stationed at the base just east of Panama City that he won't ask them or their families to return until their safety is guaranteed. The base was evacuated in advance of the Category 4 storm that struck the Gulf Coast on Wednesday afternoon with 155 mph winds and a strong storm surge.
Helicopter video by Brandon Clement of the damaged base shows roofs ripped off hangars and a fighter jet on display toppled onto the ground.
In his letter posted on the base's Facebook page, Laidlaw says crews need to clear trees from roads, repair power lines and "assess the structural integrity of our buildings" before anyone returns.
Travis AFB says it's providing critical humanitarian aid.
"Two U.S. Air Force C-17 Globemaster IIIs will depart Travis Air Force Base, California, during the early morning hours of Oct. 12, en route to Tyndall Air Force Base, Florida, to deliver a site survey team, also known as an Alpha Mike, and a Contingency Response Element," said Travis AFB in a statement.
The Associated Press contributed to this report.