OVER THE ATLANTIC OCEAN—As an Air Force Hurricane Hunter cargo plane searched for the precise center of Hurricane Florence, First Lt. Garrett Black, a meteorologist, marveled at the sheer size of the storm, which stretched hundreds of miles.
“It’s going to be a beast,” said Lt. Black, an aerial reconnaissance weather officer with the 53rd Weather Reconnaissance Squadron.
The Biloxi, Miss.-based Hurricane Hunters fly in and out of tropical cyclones to detect specific information about storms that satellite imagery, storm modeling and other technologies can’t pick up. They have been used since the mid-20th century, when the Hurricane Hunters group was formed by World War II pilots with experience flying in dangerous conditions.
“The satellites are good at picking up the visible stuff from a top-down perspective,” said Capt. Ben Blair, a pilot. “But we actually get the temperature, the pressure, wind speed, dew point and all that good stuff from inside the storm itself, from the core.”
The data collected during Tuesday’s flight prompted National Hurricane Center forecasters to raise their estimate of Florence’s wind speeds in an update less than two hours later.
Wednesday’s flight determined that wind speeds in the Category 3 hurricane had decreased to near 125 miles per hour with higher gusts. It will approach the coast off the Carolinas late Thursday and Friday.
Hurricane Hunter flights to track Florence began Monday and have taken place around the clock since. The last flight will be just before the storm makes landfall. A massive and slow-moving storm like 2017’s Hurricane Harvey can require more than 10 flights to monitor, Lt. Black said.
The Hurricane Hunters’ crews and 10 planes are part of the Air Force Reserve’s 403rd Wing and funded by the U.S. Department of Defense. The flights and research are funded by the Department of Commerce, as is the National Hurricane Center.
While traversing Florence on Tuesday, the plane moved in a series of triangles to reach set points for dropping sensors, always making left turns, to work with the rotation of the storm rather than against it, according to Capt. Blair.
The plane typically travels slower and lower than a commercial aircraft, flying through storms at about 5,000 to 10,000 feet and 200 mph, Capt. Blair said. A commercial plane typically flies at about 35,000 feet and more than 500 mph.
“If you get too fast going through that kind of severe turbulence, it can bend things on the aircraft,” said Capt. Blair, who has flown 60 flights into hurricanes.
To gather data, Staff Sgt. Nathan Calloway, the mission’s loadmaster, launched a series of cardboard-wrapped capsules, each packed with $700 of electronic sensors through a chute. Each capsule, called a dropsonde, was dropped at scheduled points along the outer band of the storm, the eyewall and the center of the eye.
The capsules fall at a rate of a half-mile per minute, sending back data three times a second on wind speed, barometric pressure and other metrics before they lose power after hitting water.
The data from the dropsondes is combined with data collected by a device fixed below the right wing called a stepped frequency microwave radiometer, or SFMR, which gauges storm intensity by converting surface brightness into wind speed. That data is sent by satellite to the National Weather Service, where it can be used by forecasters within 20 minutes.
As the flight made a second pass through the storm Tuesday, the converted WC-130J Hurricane Hunter cargo plane shook—a result of the plane hitting gusts of wind as high as 167 mph.
When the plane entered the eye, the winds died, the skies brightened and the ride became smooth, with occasional patches of blue sky. The eye was estimated at 36 miles in diameter, Capt. Blair said.
Lt. Black said the eyewall was getting stronger, a sign that the storm was strengthening. The winds also rose significantly between the first and second passes.
“This thing is not messing around,” Lt. Black said.
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