TAMPA — Jutting out into Hillsborough Bay, MacDill Air Force Base sits in a primary flood zone.
And now officials at the home of two major commands fighting wars against violent extremists are deciding whether to bug out in advance of Hurricane Irma. It is currently a Category 5 monster menacing much of Florida and expected to make landfall in the state sometime over the weekend.
MacDill is in what Hillsborough County considers Flood Zone A and would have to evacuate if so ordered by county emergency management officials.
As of Wednesday evening, that order had not been given but officials on base, home to about 18,000 military and civilian personnel, are considering making their own decision on whether to evacuate.
"There is currently no change in duty hours for personnel assigned to MacDill," said Air Force 2nd Lt. Allison Mills, a spokeswoman for the 6th Air Mobility Wing, the base host unit. "The safety of our airmen is paramount, and base leaders will provide information in a timely manner."
For U.S. Special Operations Command, which coordinates the fight against violent extremists around the globe and provides trained and equipped commandos to the individual services, the primary relocation area would be the Washington, D.C., region, SOCom spokesman Ken McGraw told the Tampa Bay Times.
Officials at U.S. Central Command, which oversees American military efforts in the Middle East and Southwest Asia, have not identified a primary relocation area. They are waiting to hear from the 6th Air Mobility Wing, MacDill's host unit, before making any relocation decisions.
The base is also home to 16 KC-135 aerial refueling tankers and several Gulfstream jets used for ferrying generals, admirals and distinguished visitors. And it may start moving aircraft off the base as early as Friday, said Mills, the 6th Wing spokeswoman.
That already happened at Naval Air Station Key West, where all personnel, families and civilians, as well as more than a dozen fighter jets and a helicopter, were evacuated beginning Tuesday night, according to Military Times.
Except for its original structure, built in 1968, SOCom's headquarters complex can withstand winds of up to 130 mph, which is the low end of a Category 3 hurricane, and storm surges of 13.5 feet, McGraw said. The original building, he said, can withstand winds of up to 100 mph, or the high end of a Category 2 hurricane. That building can also withstand storm surges of up to eight feet, McGraw said.
By comparison, Wednesday evening, Irma's speed was clocked at 185 mph, according to the National Hurricane Center.
CentCom officials declined to offer specifics on what kinds of wind and water forces their building can handle. When it opened in 2011, officials said the four-story, $80 million structure was built to handle hurricane force winds and explosions.
Since 1990, the base has required all new construction to start at a minimum of 11.5 feet above sea level. That includes the headquarters for CentCom, additions since 2007 to the SOCom headquarters, and many other buildings on base. The aircraft hangars were built long before the new sea level rules.
Aside from the height requirement, base officials say they have installed measures to eliminate erosion from storm surges of three feet or less.
"For imminent storms that look like they would hit the installation, above a Category 1, the base would evacuate per state and county recommendations," Robert Moore, deputy director of the 6th Civil Engineering Squadron, told the Times last year.
The base has about two dozen other units.
So far, "it's business as usual" at Special Operations Command Central, overseeing commando operations in the CentCom region, said Army Maj, Allen Hill, a spokesman.
"The command here ... is providing as much time needed for service members to prepare their families and their homes for Irma's arrival," said Hill. "This includes prepping their homes physically and evacuation of family members to safer locations."
The Joint Communications Support Element, which has about 500 personnel and provides advanced communications systems in the field, could move equipment to the Hillsborough County Fairgrounds if an evacuation were ordered, said Tom Wilson, the element's chief of staff.
Marine Forces Central Command, providing Marines to the CentCom commander, has relocation areas inside and outside Florida, said Maj. Brad Avots, a command spokesman.
Contact Howard Altman at hal[email protected] or (813) 225-3112. Follow @haltman.