Structure of the Eye and Eyewall of Hurricane Hugo (1989)

Marks, Frank D.; Black, Peter G.; Montgomery, Michael T.; Burpee, Robert W.
April 2008
Monthly Weather Review;Apr2008, Vol. 136 Issue 4, p1237
Academic Journal
On 15 September 1989, one of NOAA’s WP-3D research aircraft, N42RF [lower aircraft (LA)], penetrated the eyewall of Hurricane Hugo. The aircraft had an engine fail in severe turbulence while passing the radius of maximum wind and before entering the eye at 450-m altitude. After the aircraft returned to controlled flight within the 7-km radius eye, it gained altitude gradually as it orbited in the eye. Observations taken during this period provide an updated model of the inner-core structure of an intense hurricane and suggest that LA penetrated an intense cyclonic vorticity maximum adjacent to the strongest convection in the eyewall [eyewall vorticity maximum (EVM)]. This EVM was distinct from the vortex-scale cyclonic circulation observed to orbit within the eye three times during the 1 h that LA circled in the eye. At the time, Hugo had been deepening rapidly for 12 h. The maximum flight-level tangential wind was 89 m s-1 at a radius of 12.5 km; however, the primary vortex peak tangential wind, derived from a 100-s filter of the flight-level data, was estimated to be 70 m s-1, also at 12.5-km radius. The primary vortex tangential wind was in approximate gradient wind balance, was characterized by a peak in angular velocity just inside the radius of maximum wind, and had an annular vorticity structure slightly interior to the angular velocity maximum. The EVM along the aircraft’s track was roughly 1 km in diameter with a peak cyclonic vorticity of 1.25 × 10-1 s-1. The larger circulation center, with a diameter >15 km, was observed within the eye and exhibited an average orbital period of 19 min. This period is about the same as that of the angular velocity maximum of the axisymmetric mean vortex and is in reasonable agreement with recent theoretical and model predictions of a persistent trochoidal “wobble” of circulation centers in mature hurricane-like vortices. This study is the first with in situ documentation of these vortical entities, which were recently hypothesized to be elements of a lower-tropospheric eye/eyewall mixing mechanism that supports strong storms.


Related Articles

  • An Estimation of Turbulent Characteristics in the Low-Level Region of Intense Hurricanes Allen (1980) and Hugo (1989). Zhang, Jun A.; Marks, Frank D.; Montgomery, Michael T.; Lorsolo, Sylvie // Monthly Weather Review;May2011, Vol. 139 Issue 5, p1447 

    This study analyzes the flight-level data collected by research aircraft that penetrated the eyewalls of category 5 Hurricane Hugo (1989) and category 4 Hurricane Allen (1980) between 1 km and the sea surface. Estimates of turbulent momentum flux, turbulent kinetic energy (TKE), and vertical...

  • The costliest hurricane. Levinson, N. // Architectural Record;Feb1990, Vol. 178 Issue 2, p144 

    Discusses the widespread and diverse damage all types of buildings suffered in Hurricane Hugo in September 1989, as it moved through the Caribbean and the Carolinas. Roof failures; Code consequences; Fate of historic buildings; Role of architects in disaster response programs.

  • Preservationists after the storm. Fijen, C.A.P. // Architectural Record;Dec1990, Vol. 178 Issue 13, p20 

    Profiles disaster-recovery efforts after Hurricane Hugo in Charleston, S. Car. with special attention to the restoration of the city's historic design. Federal and local initiatives for restoration.

  • A hurricane hits home. Robinson, J.F. // Essence (Essence);Apr90, Vol. 20 Issue 12, p38 

    Recounts the author's shattered illusions of permanence and safety after living through Hurricane Hugo on St. Thomas in the Caribbean.

  • Train Caribbean victims in skills needed to rebuild their homes, Jackson says. Cheers, D.M. // Jet;10/23/89, Vol. 77 Issue 3, p22 

    Reports on the Rev. Jesse Jackson's visit to Caribbean islands hard hit by Hurricane Hugo, where he called for training island youths in rebuilding skills. Damage estimates are reported.

  • After Hugo, a better South Carolina. Cribb, D. // Soil & Water Conservation News;Nov/Dec91, Vol. 12 Issue 4, p4 

    Looks at the work of Soil Conservation Service employees in South Carolina to repair the effects of Hurricane Hugo. Emergency Watershed Protection (EWP) program began October 1989, finished May 1991; Cost; Individual contracts sponsored by localunits of government; Concentrated on urban area;...

  • Historic oaks stood fast. Hoss, P. // American Forests;Jan/Feb91, Vol. 97 Issue 1/2, p66 

    Reports that Hurricane Hugo could not topple four historic live oaks, including the Washington Oak at Hampton Plantation State Park, which was alive the day George Washington visited the plantation in 1791. Constitution Trees; Other survivors; More.

  • `Hugo is a killer.' Morganthau, T.; Manly, H. // Newsweek;10/2/1989, Vol. 114 Issue 14, p18 

    Discusses the damage inflicted by Hurricane Hugo on North and South Carolina, Virginia, and the Caribbean, in terms of costs to rebuild, injury, and after-effects on the economies.

  • Looking... McCloskey, Mercy // Caribbean Business;10/1/1998, Vol. 26 Issue 39, p40 

    Recaps the news stories in the aftermath of Hurricane Hugo which hit Puerto Rico during September 18, 1989. How Hurricane Hugo exposed the government of Puerto Rico's unpreparedness to handle any hurricane; Impact of Hurricane Hugo on Puerto Rico's communications; Details on the construction...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics