JOINT BASE PEARL HARBOR-HICKAM, Hawaii (AFNS) --
As Hawaii recovers from the one-two punch from Hurricanes Iselle and Julio, the 53rd Weather Reconnaissance Squadron, better known as the Air Force Reserve’s Hurricane Hunters, spent close to a week providing hurricane reconnaissance support, as well as helping with rescue efforts and data research.
The squadron launched aircraft from the island of Oahu during the storm threats and flew eight missions into Iselle and five into Julio during their stay.
Iselle, which at one point was a Category 4 hurricane, weakened into a tropical storm before it made landfall on the Big Island Friday, Aug. 8, while Hurricane Julio spared the islands moving north of Hawaii Sunday afternoon, Aug. 10.
The deployment to Hickam was due to the threat of severe weather to the Hawaiian Islands and was considered a rare event since hurricanes typically don't make their trek intact all the way to the islands, said Maj. Jon Brady, 53rd WRS aerial reconnaissance weather officer.
Hawaii has been hit by three hurricanes since 1952, the last of which was Hurricane Iniki in 1992.
A hurricane-force storm hitting Hawaii is rare due to three factors; water too cold to sustain intensity, shear winds that threaten to topple a storm over and disorganize its wind-field flow, and a desert of dry air that chokes away its power, said Brady.
"I've been doing this 14 years, and this is the first time I've had two storms back-to-back on one deployment, where I hit one storm, go into crew rest, and the next day fly into another storm, said Maj. Sean Cross, 53rd WRS pilot. "And, they're both major hurricanes at some point."
Due to the rareness of a hurricane hitting Hawaii and the uniqueness of a second hurricane trailing, the Central Pacific Hurricane Center was happy see the Hunters.
"The data they provided to us was vital," said Tom Birchard, the senior forecaster and hurricane specialist for CPHC. "It helped immensely. A lot of times we are taking educated guesses with the wind radii and wind field. Satellite data can only give us so much info; the data from the aircraft are ground truth."
That ground-truth data that the CPHC forecasters enjoy provides real-time assistance to emergency managers on the ground and helps them with weather watch and warning decisions.
"Seventy-five percent of that analysis is weighted based on the weather data gathered by the aircraft," said Birchard.
On Sunday, Aug. 10, the Hurricane Hunters assisted the U.S. Coast Guard with locating and rescuing three people north of the Hawaiian Islands in the Pacific Ocean.
A 42-foot sailboat had sent a distress mayday signal Sunday. The captain of the boat radioed that his engine had blown, and he was taking on water. To make matters worse, the captain also relayed his location, which was northeast of Hurricane Julio in an area projected to have 40-to-50-foot swells. With the boat's engine gone, and one sail ripped to shreds, the three people on board needed immediate attention.
"The latitude, longitude coordinates at the time of the mayday call placed the sailboat near the northeast side of the eye wall with approximately 55 knots of wind," said Tom Birchard, a senior forecaster and hurricane specialist with the Central Pacific Hurricane Center.
It was in a dangerous place in the core of the wind field, said Birchard.
The Hurricane Hunters, who had just finished collecting data from the eye of Hurricane Julio, turned back toward the storm and began the search.
A stroke of luck had occurred for all parties involved in the rescue mission.
"We had already fueled up the plane for a 10-hour mission, but our second storm fix requirements were cancelled, which meant we had extra fuel to search for the plane," said Williams.
As the Hunters neared the last known location of the endangered sailboat, they dropped to a low altitude to begin a visual search. Initially, they were not able to see the boat due to the weather, but once they got closer, they were able to hear the mayday signal and worked their way toward the disabled craft.
"One of the Navy oceanographers spotted the boat," said Williams. "If he hadn't seen that, we might have gone by."
"It was complicated to find the boat," said Tech. Sgt. Jenna Daniels, the loadmaster for the flight. " Once we got down below the cloud-level, we spotted it pretty quickly."
"I was working with a superstar crew," said Williams. "I had a lot of useful input from the crew, which helped me make quick and sound decisions. All we could do was stay calm with these guys on the radio. Somehow it all came together. Everyone was working together as a team and handled the situation well. It was a hug morale boost for us to find them."
Once the location was confirmed, the mission was turned over to a U.S. Coast Guard C-130.
"We were very lucky to have a Hurricane Hunter WC-130J nearby that bought us some time and offered a great sense of hope to the sailboat to see the aircraft flying above," said U.S. Coast Guard Lt. Cmdr. Jason Hagen, the command duty officer at the U.S. Coast Guard Joint Rescue Coordination Center.
The Hurricane Hunters also worked with the Navy’s research contingent of the Naval Academy’s Training and Research in Oceanic and Atmospheric Processes in Tropical Cyclones , or TROPIC, gathering storm data.
"This deployment provides us with a unique opportunity," said Navy Cmdr. (Dr.) Elizabeth Sanabia, a researcher and associate chair with the Naval Academy's Department of Oceanography. "We haven't had a (Category 3) hurricane in the Atlantic for quite some time. Also, because Julio is following closely behind Iselle, we can collect data that will tell us how these storms interact."
While the Hurricane Hunters were busy with their normal mission of gathering the real-time storm data for the forecasters at the National Hurricane Center and Central Pacific Hurricane Center, the Naval researchers were gathering data for a study to determine how the relationship between the ocean and hurricanes works. The researchers use specialized buoys, Airborne/Air Expendable Bathythermograph or AXBT, that were dropped out of a modified launch tube in the back of the WC-130J. The buoys send data by a radio signal from the ocean surface while diving down 200 feet under the water giving Naval personnel a column of data to examine.
"This mission was based on a field research program in 2008 where it was shown that if you have information about the ocean, some models can make better forecasts," said Sanabia.
According to Sanabia, the research will help meteorologists develop an understanding of the relationship between salinity and temperature of the ocean and storm strength.
"Most of the forecast models today just draw data from the atmosphere itself, but since hurricanes draw heat from the ocean, newer models called "coupled models" look at both the ocean and the atmosphere and need the information from the ocean to be accurate," she said.
Naval personnel set up and dropped AXBT buoys during each reconnaissance flight into Iselle and Julio, which radio back information about the ocean's temperature, said Maj. Jon Brady, a 53rd WRS aerial reconnaissance weather officer.
"The partnership between the Navy researchers and our squadron is great because it benefits the forecasts with very little extra costs," said Brady. "We are already flying these missions, while they are using the back half of our aircraft to conduct this research.
"The knowledge gained is also helpful. They are helping with future forecasts," he added. "They are able to prove how much ocean cooling occurs as [storms] go by. The Navy's AXBT buoys provide key ocean temperature measurements which are crucial to intensity forecasting for hurricanes. Warmer ocean temperatures increase storm strength, while colder temperatures will weaken them. Knowing the actual water temperatures ahead of an approaching storm is very important aspect of intensity forecasting."
The partnership between the Navy TROPIC research team and the Hurricane Hunters is in its fourth year and is an ongoing partnership to help the National Hurricane Center increase the accuracy of hurricane forecasts by incorporating ocean data from beneath tropical systems into air-ocean coupled prediction models, which use data from the air and the ocean to obtain ocean temperature data to use in forecasts.
With Julio dying and heading off to die in the colder waters North of Hawaii, the Hunters head back to Biloxi, Mississippi, this week ready for the next storm, which is brewing in the Atlantic basin.