Hurricane hunters are in the sky as Hurricane Ian intensifies over the Florida coast, doing the nearly impossible by flying straight through the eye of the storm. Scientists aboard these planes fly over hurricane zones, gathering data that satellites can’t use for forecasting and relaying it to the National Hurricane Center.
NOAA’s 2022 Hurricane Program is led by University of Miami meteorologist and professor Jason Dunnion. He talks about overcoming a cyclone in the P-3 Orion and how they are using cutting edge technology to track its progress in real time.
How does a hurricane hunter handle a storm?
A flying lab will be sent into the eye of a hurricane, even a Category 5 storm. We send data to forecasters and climate modelers while in the air. We regularly fly right into the eye of a storm in P-3s. Think of it as X: we make multiple passes through the storm while on a mission.
These may be Category 5 hurricanes or emerging. Our average cruising altitude is approximately 10,000 feet, which puts us about a quarter of the way between the surface of the water and the top of the storm. If we want to get accurate Hurricane Center data, we need to go through the eye of the storm.
Can you describe what scientists experience on these flights?
Dorian was the most intense of 2019. Near the Bahamas, the storm quickly strengthened to a Category 5 with winds of 185 mph. It felt like flying. Passing through Dorian’s eyewall, they all buckled. A downdraft can make you lose hundreds of feet in seconds, or an updraft can help you gain them.
It’s like riding a roller coaster, except you can’t predict the next up or down. We hit 3 to 4 Gs. During a rocket launch, astronauts feel this. We can also achieve zero G for a few seconds and everything unfastened will float away.
Even during the storm, scientists like me work on computers. We assess the quality of the data and send it to the modeling centers and the National Hurricane Center after a technician in the back fires a probe from the belly of the plane.
What do these flights teach you about hurricanes?
Understanding why storms escalate quickly is a goal. A 35 mph gale per day is building rapidly. This is like a Category 1 storm quickly becoming a Category 3 storm. Ida (2021), Dorian (2019) and Michael (2018) quickly strengthened. This can be dangerous if it happens near land.
Because rapid intensification can happen quickly, we need to be with hurricane hunters to take measurements as the storm forms. Rapid amplification is currently unpredictable. The ingredients can come together quickly: Deep ocean warm?
Is the atmosphere of the storm cool and humid? Favorable winds? The inner core is also being explored. What is the structure and consolidation of the storm? Satellites can give forecasters a basic perspective, but hurricane hunters have to get inside the storm to assess it.
So what does the rapidly intensifying storm look like?
Think of a spinning top and you’ll have an idea of how hurricanes like to be. This means we prioritize congruence. Low-level circulation occurring only a few kilometers over the ocean may not be in sync with the storm’s mid-level circulation occurring at heights of 6 or 7 kilometers in a storm that is still disorganized.
It looks like the storm may be harmful. However, if we return to the storm a few hours later, we may find that its two cores are now more aligned. An indication of possible rapid escalation. We also analyze the region above the water known as the boundary layer.
Air is drawn into a hurricane at lower levels, pushed up into the eyewall, and finally released at the peak of the storm, moving away from the eye. As this is the case, the eyewall experiences huge updrafts.
If we want to know how the winds are blowing in the boundary layer, we can check the data from our falling probe or tail Doppler radar. Are we seeing a surge of moist air near the eye of the storm? A storm can take a deeper breath if it has a thick boundary layer.
The framework is also being explored. Although the storm may appear strong from space, when we zoom in with the radar and find that the structure is sloppy or the eye is full of clouds, we know that the storm is not yet ready to rapidly intensify.
However, the structure may begin to shift rapidly during this flight. Noticing how you feel in a storm as you inhale, rise, and exhale can tell you a lot. It may be an indication of a growing storm if breathing appears normal.
What tools do you use to measure and predict hurricane behavior?
We need instruments to measure the ocean and the atmosphere. Ocean heat and moisture generate storms, not winds. The probes measure temperature, humidity, pressure and wind speed every 15 feet to the ocean’s surface. The National Hurricane Center and modeling centers use this data to better simulate the atmosphere.
A P-3 has a laser that can monitor temperature, humidity and pollutants from the plane to the surface of the ocean. This shows how juicy the atmosphere is and how well suited it is to fuel a storm. The CRL operates continuously along the entire flight path, creating a temperature and humidity curtain under the aircraft.
Tail Doppler radars measure how moisture droplets blow through the air to determine wind speed. It’s like an x-ray of the storm’s wind field in 3D. This is not satellite. We launch AXBT ocean probes ahead of storms. These probes measure water temperature 300 feet down.
Surface temperatures of 26.5 degrees Celsius (80 degrees Fahrenheit) and higher are favorable for hurricanes, although depth heat is also significant. If the surface of the ocean is 85 F, but it is much colder at a depth of 50 feet, the hurricane will quickly mix with the cold water and weaken. Deep warm water, especially in the Gulf eddies, can fuel a hurricane.
Small drones that can be launched from the belly of the P-3 are another new technology we are experimenting with this year. They are like a flying weather station, measuring 7 to 9 feet in range. The strength of the storm can be gauged by the pressure fluctuations that one of these eye-placed drones can measure.
Another important piece of information for forecasters would be the location of the strongest winds, which could be determined by dropping a drone into the eyewall and circling there. It is also difficult to get reliable data from the boundary layer because aircraft cannot safely operate there.