• Blake, E. S., , T. B. Kimberlain, , R. J. Berg, , G. P. Cangialosi, , and J. L. Beven II, 2013: Tropical cyclone report: Hurricane Sandy. National Hurricane Center Tech. Rep. AL182012, 157 pp. [Available online at www.nhc.noaa.gov/data/tcr/AL182012_Sandy.pdf.]

  • Charney, J. G., , and A. Eliassen, 1964: On the growth of the hurricane depression. J. Atmos. Sci., 21, 6875, doi:10.1175/1520-0469(1964)021<0068:OTGOTH>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Cheung, K. K. W., , and R. L. Elsberry, 2002: Tropical cyclone formations over the western North Pacific in the navy operational global atmospheric prediction system forecasts. Wea. Forecasting, 17, 800820, doi:10.1175/1520-0434(2002)017<0800:TCFOTW>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Dunkerton, T. J., , M. T. Montgomery, , and Z. Wang, 2009: Tropical cyclogenesis in a tropical wave critical layer: Easterly waves. Atmos. Chem. Phys., 9, 55875646, doi:10.5194/acp-9-5587-2009.

    • Search Google Scholar
    • Export Citation
  • Ferreira, R. N., , and W. H. Schubert, 1997: Barotropic aspects of ITCZ breakdown. J. Atmos. Sci., 54, 261285, doi:10.1175/1520-0469(1997)054<0261:BAOIB>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Gray, W. M., , and R. W. Jacobson Jr., 1977: Diurnal variation of deep cumulus convection. Mon. Wea. Rev., 105, 11711188, doi:10.1175/1520-0493(1977)105<1171:DVODCC>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Hack, J. J., , W. H. Schubert, , D. E. Stevens, , and H.-C. Kuo, 1989: Response of the Hadley circulation to convective forcing in the ITCZ. J. Atmos. Sci., 46, 29572973, doi:10.1175/1520-0469(1989)046<2957:ROTHCT>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Harr, P. A., , R. L. Elsberry, , and J. C. Chan, 1996: Transformation of a large monsoon depression to a tropical storm during TCM-93. Mon. Wea. Rev., 124, 26252643, doi:10.1175/1520-0493(1996)124<2625:TOALMD>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Haynes, P. H., , and M. E. McIntyre, 1987: On the evolution of vorticity and potential vorticity in the presence of diabatic heating and frictional or other forces. J. Atmos. Sci., 44, 828841, doi:10.1175/1520-0469(1987)044<0828:OTEOVA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Holland, G. J., 1983: Angular momentum transports in tropical cyclones. Quart. J. Roy. Meteor. Soc., 109, 187209, doi:10.1002/qj.49710945909.

    • Search Google Scholar
    • Export Citation
  • Holton, J. R., 2004: An Introduction to Dynamic Meteorology. 4th ed. Academic Press, 535 pp.

  • Ide, K., , D. Small, , and S. Wiggins, 2002: Distinguished hyperbolic trajectories in time-dependent fluid flows: Analytical and computational approach for velocity fields defined as data sets. Nonlinear Processes Geophys., 9, 237263, doi:10.5194/npg-9-237-2002.

    • Search Google Scholar
    • Export Citation
  • Killworth, P. D., , and M. E. McIntyre, 1985: Do Rossby-wave critical layers absorb, reflect, or over-reflect? J. Fluid Mech., 161, 449492, doi:10.1017/S0022112085003019.

    • Search Google Scholar
    • Export Citation
  • Kilroy, G., , and R. K. Smith, 2012: A numerical study of rotating convection during tropical cyclogenesis. Quart. J. Roy. Meteor. Soc., 139, 1255–1269, doi:10.1002/qj.2022.

    • Search Google Scholar
    • Export Citation
  • Landsea, C. W., 1993: A climatology of intense (or major) Atlantic hurricanes. Mon. Wea. Rev., 121, 17031713, doi:10.1175/1520-0493(1993)121<1703:ACOIMA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Malhotra, N., , and S. Wiggins, 1998: Geometric structures, lobe dynamics, and Lagrangian transport in flows with aperiodic time-dependence, with applications to Rossby wave flow. J. Nonlinear Sci., 8, 401456, doi:10.1007/s003329900057.

    • Search Google Scholar
    • Export Citation
  • Mancho, A. M., , D. Small, , S. Wiggins, , and K. Ide, 2003: Computation of stable and unstable manifolds of hyperbolic trajectories in two-dimensional, aperiodically time-dependent vector fields. Physica D, 182, 188222, doi:10.1016/S0167-2789(03)00152-0.

    • Search Google Scholar
    • Export Citation
  • Montgomery, M. T., , and R. K. Smith, 2014: Paradigms for tropical cyclone intensification. Aust. Meteor. Oceanogr. J., 64, 37–66.

  • Montgomery, M. T., , L. L. Lussier III, , R. W. Moore, , and Z. Wang, 2010a: The genesis of Typhoon Nuri as observed during the Tropical Cyclone Structure 2008 (TCS-08) field experiment—Part 1: The role of the easterly wave critical layer. Atmos. Chem. Phys., 10, 98799900, doi:10.5194/acp-10-9879-2010.

    • Search Google Scholar
    • Export Citation
  • Montgomery, M. T., , Z. Wang, , and T. J. Dunkerton, 2010b: Coarse, intermediate and high resolution numerical simulations of the transition of a tropical wave critical layer to a tropical storm. Atmos. Chem. Phys., 10, 10 803–10 810, doi:10.5194/acp-10-10803-2010.

    • Search Google Scholar
    • Export Citation
  • Montgomery, M. T., and et al. , 2012: The Pre-Depression Investigation of Cloud-Systems in the Tropics (PREDICT) experiment. Bull. Amer. Meteor. Soc., 93, 153172, doi:10.1175/BAMS-D-11-00046.1.

    • Search Google Scholar
    • Export Citation
  • NASA, cited 2015: HS3 hurricane mission. [Available online at www.nasa.gov/mission_pages/hurricanes/missions/hs3/#.VPdnWfx4o2Y.]

  • Okubo, A., 1970: Horizontal dispersion of floatable particles in the vicinity of velocity singularities such as convergences. Deep-Sea Res. Oceanogr. Abstr., 17, 445454, doi:10.1016/0011-7471(70)90059-8.

    • Search Google Scholar
    • Export Citation
  • Riemer, M., , and M. T. Montgomery, 2011: Simple kinematic models for the environmental interaction of tropical cyclones in vertical wind shear. Atmos. Chem. Phys., 11, 93959414, doi:10.5194/acp-11-9395-2011.

    • Search Google Scholar
    • Export Citation
  • Rutherford, B., , and M. T. Montgomery, 2012: A Lagrangian analysis of a developing and non-developing disturbance observed during the PREDICT experiment. Atmos. Chem. Phys., 12, 11 35511 381, doi:10.5194/acp-12-11355-2012.

    • Search Google Scholar
    • Export Citation
  • Schecter, D. A., , and M. T. Montgomery, 2006: Conditions that inhibit the spontaneous radiation of spiral inertia–gravity waves from an intense mesoscale cyclone. J. Atmos. Sci., 63, 435456, doi:10.1175/JAS3641.1.

    • Search Google Scholar
    • Export Citation
  • Schubert, W. H., , P. E. Ciesielski, , D. E. Stevens, , and H.-C. Kuo, 1991: Potential vorticity modeling of the ITCZ and the Hadley circulation. J. Atmos. Sci., 48, 14931509, doi:10.1175/1520-0469(1991)048<1493:PVMOTI>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Shen, B.-W., , M. DeMaria, , J.-L. Li, , and S. Cheung, 2013: Genesis of Hurricane Sandy (2012) simulated with a global mesoscale model. Geophys. Res. Lett., 40, 49444950, doi:10.1002/grl.50934.

    • Search Google Scholar
    • Export Citation
  • Smith, R. K., , M. T. Montgomery, , and N. Van Sang, 2009: Tropical cyclone spin-up revisited. Quart. J. Roy. Meteor. Soc., 135, 13211335, doi:10.1002/qj.428.

    • Search Google Scholar
    • Export Citation
  • Wang, Z., , M. T. Montgomery, , and T. J. Dunkerton, 2009: A dynamically-based method for forecasting tropical cyclogenesis location in the Atlantic sector using global model products. Geophys. Res. Lett., 36, L03801, doi:10.1029/2008GL035586.

    • Search Google Scholar
    • Export Citation
  • Wang, Z., , M. T. Montgomery, , and T. J. Dunkerton, 2010a: Genesis of pre–Hurricane Felix (2007). Part I: The role of the easterly wave critical layer. J. Atmos. Sci., 67, 17111729, doi:10.1175/2009JAS3420.1.

    • Search Google Scholar
    • Export Citation
  • Wang, Z., , M. T. Montgomery, , and T. J. Dunkerton, 2010b: Genesis of pre–Hurricane Felix (2007). Part II: Warm core formation, precipitation evolution, and predictability. J. Atmos. Sci., 67, 17301744, doi:10.1175/2010JAS3435.1.

    • Search Google Scholar
    • Export Citation
  • Wang, Z., , M. T. Montgomery, , and C. Fritz, 2012: A first look at the structure of the wave pouch during the 2009 PREDICT–GRIP dry runs over the Atlantic. Mon. Wea. Rev., 140, 11441163, doi:10.1175/MWR-D-10-05063.1.

    • Search Google Scholar
    • Export Citation
  • Weiss, J., 1991: The dynamics of enstrophy transfer in two-dimensional hydrodynamics. Physica D, 48, 273294, doi:10.1016/0167-2789(91)90088-Q.

    • Search Google Scholar
    • Export Citation
  • Wiggins, S., , and J. Guckenheimer, 1992: Chaotic transport in dynamical systems. Phys. Today, 45, 68, doi:10.1063/1.2809741.

  • Willoughby, H. E., 1990: Gradient balance in tropical cyclones. J. Atmos. Sci., 47, 265274, doi:10.1175/1520-0469(1990)047<0265:GBITC>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
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Examining the Roles of the Easterly Wave Critical Layer and Vorticity Accretion during the Tropical Cyclogenesis of Hurricane Sandy

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  • 1 Naval Postgraduate School, Monterey, California
  • | 2 NorthWest Research Associates, Bellevue, Washington
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Abstract

The tropical cyclogenesis sequence of Hurricane Sandy is examined. It is shown that genesis occurs within a recirculating Kelvin cat’s-eye flow of a westward-propagating tropical wave. The cat’s-eye flow is able to provide a protective environment for the mesoscale vortex to grow and is characterized by gradual column moistening and increased areal coverage of deep cumulus convection. These findings are generally consistent with a recently proposed tropical cyclogenesis sequence referred to as the “marsupial paradigm.” Sandy’s cyclogenesis provides a useful illustration of the marsupial paradigm within a partially open recirculating region, with the opening located south of the pouch center. It is suggested that the opening acts to enhance the genesis process because it is adjacent to an environment characterized by warm, moist air, conditions favorable for tropical cyclogenesis. From a dynamical perspective, accretion of low-level cyclonic vorticity filaments into the developing vortex from several sources (the South American convergence zone, an easterly wave located west of the pre-Sandy wave, and cyclonic vorticity generated along Hispaniola) is documented. Organization and growth of the nascent storm is enhanced by this accretion of cyclonic vorticity. A Lagrangian trajectory analysis is used to assess potential contributions to Sandy’s spinup from a Caribbean gyre and the easterly wave that formed Hurricane Tony. This analysis indicates that these features are outside of the Lagrangian flow boundaries that define the pre-Sandy wave and do not directly contribute to spinup of the vortex. Finally, the effectiveness of forecasts from the U.S. and European operational numerical weather prediction models is discussed for this case.

Supplemental information related to this paper is available at the Journals Online website: http://dx.doi.org/10.1175/MWR-D-14-00001.s1.

Current affiliation: Research Aviation Facility, National Center for Atmospheric Research, Broomfield, Colorado.

Corresponding author address: Louis L. Lussier III, 10802 Airport Ct., Broomfield, CO 80021. E-mail: lussier@ucar.edu

Abstract

The tropical cyclogenesis sequence of Hurricane Sandy is examined. It is shown that genesis occurs within a recirculating Kelvin cat’s-eye flow of a westward-propagating tropical wave. The cat’s-eye flow is able to provide a protective environment for the mesoscale vortex to grow and is characterized by gradual column moistening and increased areal coverage of deep cumulus convection. These findings are generally consistent with a recently proposed tropical cyclogenesis sequence referred to as the “marsupial paradigm.” Sandy’s cyclogenesis provides a useful illustration of the marsupial paradigm within a partially open recirculating region, with the opening located south of the pouch center. It is suggested that the opening acts to enhance the genesis process because it is adjacent to an environment characterized by warm, moist air, conditions favorable for tropical cyclogenesis. From a dynamical perspective, accretion of low-level cyclonic vorticity filaments into the developing vortex from several sources (the South American convergence zone, an easterly wave located west of the pre-Sandy wave, and cyclonic vorticity generated along Hispaniola) is documented. Organization and growth of the nascent storm is enhanced by this accretion of cyclonic vorticity. A Lagrangian trajectory analysis is used to assess potential contributions to Sandy’s spinup from a Caribbean gyre and the easterly wave that formed Hurricane Tony. This analysis indicates that these features are outside of the Lagrangian flow boundaries that define the pre-Sandy wave and do not directly contribute to spinup of the vortex. Finally, the effectiveness of forecasts from the U.S. and European operational numerical weather prediction models is discussed for this case.

Supplemental information related to this paper is available at the Journals Online website: http://dx.doi.org/10.1175/MWR-D-14-00001.s1.

Current affiliation: Research Aviation Facility, National Center for Atmospheric Research, Broomfield, Colorado.

Corresponding author address: Louis L. Lussier III, 10802 Airport Ct., Broomfield, CO 80021. E-mail: lussier@ucar.edu

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