Into the Eye of the Storm

What exactly is a hurricane? How do they impact aviation operations? Can you fly an aircraft into a hurricane?

Warm ocean water is a hurricane's primary fuel source, as increasing evaporation of water from the ocean surface from warmer waters will result in a stronger storm. The vertical structure of a hurricane will weaken with height, has high pressure aloft, and is a warm-core low. Since a hurricane weakens with height, the area of low pressure at the surface may become an area of high pressure "above 12 km, 40,000 ft..." (Ahrens and Henson, 2018). Warm-core lows are when low-pressure areas are warmer at the center. The downdrafts of air create a calm area in the middle of the hurricane called the "eye" where there are typically clear skies. The strongest winds occur near the surface and rotate around the eye in a counterclockwise motion in the Northern Hemisphere and in a clockwise motion in the Southern Hemisphere. Around a hurricane, the isobars are more circular and the pressure gradient is steeper with no fronts, so the winds are stronger. NOAA’s Gulfstream IV-SP which can fly high, fast, and far with a range of 4,000 nautical miles and a cruising altitude of 45,000 ft, paints a detailed picture of weather systems in the upper atmosphere surrounding developing hurricanes (NOAA, 2020). Flying through the eyewall is the most violent part of the aircraft's journey to the eye of the hurricane. The flight crew prepares by securing down all of the equipment and putting on extra seat belt harnesses to prepare for the brief moments of intense turbulence. While flying through the eyewall, intense winds and turbulence occur, visibility is reduced to almost nothing, and heavy rain batters the aircraft. Once the aircraft breaks through the eyewall and into the eye, the air becomes calm, the skies are clear above, and there is no rain. The scientists aboard the aircraft deploy "drop-wind-sonde as the P-3 flies through the hurricane. These instruments continuously transmit measurements of pressure, humidity, temperature, and wind direction and speed as they fall toward the sea, providing a detailed look at the structure of the storm and its intensity... the Tail Doppler radar and lower fuselage radar systems, meanwhile, scan the storm vertically and horizontally, giving scientists and forecasters a real-time look at the storm. The P-3s can also deploy probes called bathythermographs that measure the temperature of the sea (NOAA, 2020). The purpose of these dangerous missions is to help locate the center of the storm and measure the pressure and surface winds around the eye. This information aids in the safety of people that live along the coasts that are more vulnerable than others during the storm. The information collected also goes to research programs that study approaching storms and work to improve forecasts. Below are pictures from the eyes of different hurricanes:

Depicted above is the eye of the infamous Hurricane Katrina, a category 5 hurricane, which took place from Aug 23, 2005, to Aug 31, 2005. The highest wind speed recorded was 174 MPH.

Depicted above is the eye of Hurricane Dorian, a category 5 hurricane, which took place from Aug 24, 2019, to Sept. 10, 2019. The highest wind speed recorded was 185 MPH.

Depicted above is the eye of Hurricane Irma, a Category 5 hurricane, which took place from Aug 30, 2017, to Sept 14, 2017. The highest wind speed recorded was 185 MPH.

References

Ahrens, C. D., & Henson, R. (2018). Meteorology Today: Introductory Weather Climate & Environment, 12th Edition. Mason, OH: Cengage Learning. Black, G. (2019, September 2). Eerie photo captures the eye of Hurricane Dorian, one of the most powerful Atlantic storms in history [Digital image]. https://www.insider.com/hurricane-dorian-video-eye-storm-heading-us-2019-9 Blancher, P. (n.d.). Incredible footage shows the eye of Hurricane Irma [Digital image].https://expressdigest.com/incredible-footage-shows-the-eye-of-the-hurricane-irma/ Inside the eye of Hurricane Katrina - August 2005 [Digital image]. (n.d.). http://www.geo.umass.edu/courses/climat/home.html NOAA. (2020, December 21). Aircraft operations. https://www.omao.noaa.gov/learn/aircraft-operations/about/hurricane-hunters