Planes from Langley Air Force Base, Virginia, and Seymour Johnson Air Force Base, North Carolina, are flying to other bases as Hurricane Joaquin menaces the East Coast.

About 30 F-22s and 10 T-38s began leaving Langley starting at 1 p.m. along with 100 airmen from the 1st and 192nd Fighter Wings, officials said. The planes and personnel are headed to Grissom Air Reserve Base, Indiana.

Langley will be closed to all non-mission essential personnel starting at 9 a.m. on Friday, but it will remain open for main base residents, according to a base news release.

More than 70 F-15Es and between two and three KC-135s from the 4th Fighter Wing and 916th Air Refueling Wing are in the process of leaving Seymour Johnson, said Capt. Joseph Alonso, a spokesman for the 4th Fighter Wing.

On Thursday afternoon, the "Hurricane Hunters" of the 53rd Weather Reconnaissance Squadron flew through Hurricane Joaquin as it passed through the Bahamas, said Master Sgt. Brian Lamar, a spokesman for the 403rd Wing.

Now a Category 4 hurricane, Joaquin had winds of 134 miles per hour and a low pressure of 937 millibars, as the Hurricane Hunters' WC-130J flew figure eights through the storm, Lamar said. The squadron will head to Savannah, Georgia, on Friday so that they can get to the storm more quickly, he said.

The Hurricane Hunters collect real-time data from inside hurricanes, and that information is often used in the models used to forecast where hurricanes will go, said Lt. Col. John Talbot, chief aerial reconnaissance weather officer for the 53rd Weather Reconnaissance Squadron.

"We provide information about what's going on right now because you can't get that information from satellites," Talbot told Air Force Times. "The only way we can get this real-time information of what's happening as the storm may be intensifying or weakening is by using aircraft."

Hurricane Joaquin has proven to be hard to predict, with some models indicating the storm may hit the Mid-Atlantic and others tracking the storm moving out to sea. Talbot attributes the difficulties predicting where the storm will go to the time of year. In October, the atmosphere begins transitioning from summer to fall, and that complicates things.

"Think of yourself going down a river in a raft and you go into an area off the side where it's just a whirlpool," he said. "As things develop in the atmosphere over time, this river of air that steers the direction of the hurricane may get more defined."