• Aiyyer, A., 2015: Recurving western North Pacific tropical cyclones and midlatitude predictability. Geophys. Res. Lett., 42, 77997807, doi:10.1002/2015GL065082.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Anwender, D., P. A. Harr, and S. C. Jones, 2008: Predictability associated with the downstream impacts of the extratropical transition of tropical cyclones: Case studies. Mon. Wea. Rev., 136, 32263247, doi:10.1175/2008MWR2249.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Archambault, H. M., D. Keyser, L. F. Bosart, C. A. Davis, and J. M. Cordeira, 2015: A Composite perspective of the extratropical flow response to recurving western North Pacific tropical cyclones. Mon. Wea. Rev., 143, 11221141, doi:10.1175/MWR-D-14-00270.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Atallah, E. H., and L. F. Bosart, 2003: The extratropical transition and precipitation distribution of Hurricane Floyd (1999). Mon. Wea. Rev., 131, 10631081, doi:10.1175/1520-0493(2003)131<1063:TETAPD>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Chang, E. K. M., M. Zheng, and K. Raeder, 2013: Medium-range ensemble sensitivity analysis of two extreme Pacific extratropical cyclones. Mon. Wea. Rev., 141, 211231, doi:10.1175/MWR-D-11-00304.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Cordeira, J. M., and L. F. Bosart, 2010: The antecedent large-scale conditions of the perfect storms of late October and early November 1991. Mon. Wea. Rev., 138, 25462569, doi:10.1175/2010MWR3280.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Danielson, R. E., J. R. Gyakum, and D. N. Straub, 2004: Downstream baroclinic development among forty-one cold-season eastern North Pacific cyclones. Atmos.–Ocean, 42, 235250, doi:10.3137/ao.420402.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Davis, C., B. Brown, and R. Bullock, 2006: Object-based verification of precipitation forecasts. Part I: Methodology and application to mesoscale rain areas. Mon. Wea. Rev., 134, 17721784, doi:10.1175/MWR3145.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • ECMWF, 2008: European Centre for Medium-Range Weather Forecasts Ensemble Prediction System—Operational archive Cycle35r3, Resolution T639L62, accessed April 2011. [Available online at http://www.ecmwf.int/en/forecasts/datasets/set-iii.].

  • Garcies, L., and V. Homar, 2009: Ensemble sensitivities of the real atmosphere: Application to Mediterranean intense cyclones. Tellus, 61A, 394406, doi:10.1111/j.1600-0870.2009.00392.x.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Glatt, I., and V. Wirth, 2014: Identifying Rossby wave trains and quantifying their properties. Quart. J. Roy. Meteor. Soc., 140, 384396, doi:10.1002/qj.2139.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Grams, C. M., and et al. , 2011: The key role of diabatic processes in modifying the upper-tropospheric wave guide: A North Atlantic case study. Quart. J. Roy. Meteor. Soc., 137, 21742193, doi:10.1002/qj.891.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Grams, C. M., S. C. Jones, and C. A. Davis, 2013a: The impact of Typhoon Jangmi (2008) on the midlatitude flow. Part II: Downstream evolution. Quart. J. Roy. Meteor. Soc., 139, 21652180, doi:10.1002/qj.2119.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Grams, C. M., S. C. Jones, C. A. Davis, P. A. Harr, and M. Weissmann, 2013b: The impact of Typhoon Jangmi (2008) on the midlatitude flow. Part I: Upper-level ridgebuilding and modification of the jet. Quart. J. Roy. Meteor. Soc., 139, 21482164, doi:10.1002/qj.2091.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Grams, C. M., S. T. K. Lang, and J. H. Keller, 2015: A quantitative assessment of the sensitivity of the downstream midlatitude flow response to extratropical transition of tropical cyclones. Geophys. Res. Lett., 42, 95219529, doi:10.1002/2015GL065764.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Griffin, K. S., and L. F. Bosart, 2014: The extratropical transition of Tropical Cyclone Edisoana (1990). Mon. Wea. Rev., 142, 27722793, doi:10.1175/MWR-D-13-00282.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hakim, G. J., and R. D. Torn, 2008: Ensemble synoptic analysis. Synoptic–Dynamic Meteorology and Weather Analysis and Forecasting: A Tribute to Fred Sanders, Meteor. Monogr., No. 55, Amer. Meteor. Soc., 147–162.

    • Crossref
    • Export Citation
  • Harr, P. A., 2010: The extratropical transition of tropical cyclones. Global Perspectives on Tropical Cyclones, From Science to Mitigation, 2nd ed. J. L. C. Chan and J. D. Kepert, Eds., World Scientific Series on Asia-Pacific Weather and Climate, Vol. 4, World Scientific, 149–176.

    • Crossref
    • Export Citation
  • Harr, P. A., and J. M. Dea, 2009: Downstream development associated with the extratropical transition of tropical cyclones over the western North Pacific. Mon. Wea. Rev., 137, 12951319, doi:10.1175/2008MWR2558.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Harr, P. A., R. L. Elsberry, and T. Hogan, 2000: Extratropical transition of tropical cyclones over the western North Pacific. Part II: The impact of midlatitude circulation characteristics. Mon. Wea. Rev., 128, 26342653, doi:10.1175/1520-0493(2000)128<2634:ETOTCO>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Harr, P. A., D. Anwender, and S. C. Jones, 2008: Predictability associated with the downstream impacts of the extratropical transition of tropical cyclones: Methodology and a case study of Typhoon Nabi (2005). Mon. Wea. Rev., 136, 32053225, doi:10.1175/2008MWR2248.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hawblitzel, D. P., F. Zhang, Z. Meng, and C. A. Davis, 2007: Probabilistic evaluation of the dynamics and predictability of the mesoscale convective vortex of 10–13 June 2003. Mon. Wea. Rev., 135, 15441563, doi:10.1175/MWR3346.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jones, S. C., and et al. , 2003: The extratropical transition of tropical cyclones: Forecast challenges, current understanding, and future directions. Wea. Forecasting, 18, 10521092, doi:10.1175/1520-0434(2003)018<1052:TETOTC>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Keller, J. H., 2012: Diagnosing the downstream impact of extratropical transition using multimodel operational ensemble prediction systems. Ph.D. thesis, Karlsruhe Institute of Technology, 172 pp. [Available online at http://digbib.ubka.uni-karlsruhe.de/volltexte/1000026043.]

  • Keller, J. H., S. C. Jones, and P. A. Harr, 2014: An eddy kinetic energy view of physical and dynamical processes in distinct forecast scenarios for the extratropical transition of two tropical cyclones. Mon. Wea. Rev., 142, 27512771, doi:10.1175/MWR-D-13-00219.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Klein, P. M., P. A. Harr, and R. L. Elsberry, 2000: Extratropical transition of western North Pacific tropical cyclones: An overview and conceptual model of the transformation stage. Wea. Forecasting, 15, 373396, doi:10.1175/1520-0434(2000)015<0373:ETOWNP>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Klein, P. M., P. A. Harr, and R. L. Elsberry, 2002: Extratropical transition of western North Pacific cyclones: Midlatitude and tropical cyclone contributions to reintensification. Mon. Wea. Rev., 130, 22402259, doi:10.1175/1520-0493(2002)130<2240:ETOWNP>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lang, S. T. K., M. Leutbecher, and S. C. Jones, 2012: Impact of perturbation methods in the ECMWF Ensemble Prediction System on tropical cyclone forecasts. Quart. J. Roy. Meteor. Soc., 138, 20302046, doi:10.1002/qj.1942.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Majumdar, S. J., K. J. Sellwood, D. Hodyss, Z. Toth, and Y. Song, 2010: Characteristics of target areas selected by the ensemble transform Kalman filter for medium-range forecasts of high-impact winter weather. Mon. Wea. Rev., 138, 28032824, doi:10.1175/2010MWR3106.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • McTaggart-Cowan, R., J. R. Gyakum, and M. K. Yau, 2003: The influence of the downstream state on extratropical transition: Hurricane Earl (1998) case study. Mon. Wea. Rev., 131, 19101929, doi:10.1175//2589.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Orlanski, I., and E. K. M. Chang, 1993: Ageostrophic geopotential fluxes in downstream and upstream development of baroclinic waves. J. Atmos. Sci., 50, 212225, doi:10.1175/1520-0469(1993)050<0212:AGFIDA>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Orlanski, I., and J. Sheldon, 1995: Stages in the energetics of baroclinic systems. Tellus, 47A, 605628, doi:10.1034/j.1600-0870.1995.00108.x.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pantillon, F., J.-P. Chaboureau, C. Lac, and P. Mascart, 2013a: On the role of a Rossby wave train during the extratropical transition of Hurricane Helene (2006). Quart. J. Roy. Meteor. Soc., 139, 370386, doi:10.1002/qj.1974.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pantillon, F., J.-P. Chaboureau, P. J. Mascart, and C. Lac, 2013b: Predictability of a Mediterranean tropical-like storm downstream of the extratropical transition of Hurricane Helene (2006). Mon. Wea. Rev., 141, 19431962, doi:10.1175/MWR-D-12-00164.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pantillon, F., J.-P. Chaboureau, and E. Richard, 2015: Remote impact of North Atlantic hurricanes on the Mediterranean during episodes of intense rainfall in autumn 2012. Quart. J. Roy. Meteor. Soc., 141, 967978, doi:10.1002/qj.2419.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Quinting, J. F., and S. C. Jones, 2016: The impact of tropical cyclones on midlatitude Rossby wave packets: A climatological perspective. Mon. Wea. Rev., 144, 20212048, doi:10.1175/MWR-D-14-00298.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Riemer, M., and S. C. Jones, 2010: The downstream impact of tropical cyclones on a developing baroclinic wave in idealized scenarios of extratropical transition. Quart. J. Roy. Meteor. Soc., 136, 617637, doi:10.1002/qj.605.

    • Search Google Scholar
    • Export Citation
  • Riemer, M., S. C. Jones, and C. A. Davis, 2008: The impact of extratropical transition on the downstream flow: An idealized modelling study with a straight jet. Quart. J. Roy. Meteor. Soc., 134, 6991, doi:10.1002/qj.189.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Ritchie, E. A., and R. L. Elsberry, 2003: Simulations of the extratropical transition of tropical cyclones: Contributions by the midlatitude upper-level trough to reintensification. Mon. Wea. Rev., 131, 21122128, doi:10.1175/1520-0493(2003)131<2112:SOTETO>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Ritchie, E. A., and R. L. Elsberry, 2007: Simulations of the extratropical transition of tropical cyclones: Phasing between the upper-level trough and tropical cyclones. Mon. Wea. Rev., 135, 862876, doi:10.1175/MWR3303.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schumacher, R. S., 2011: Ensemble-based analysis of factors leading to the development of a multiday warm-season heavy rain event. Mon. Wea. Rev., 139, 30163035, doi:10.1175/MWR-D-10-05022.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sippel, J. A., and F. Zhang, 2008: A probabilistic analysis of the dynamics and predictability of tropical cyclogenesis. J. Atmos. Sci., 65, 34403459, doi:10.1175/2008JAS2597.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Souders, M. B., B. A. Colle, and E. K. M. Chang, 2014: The climatology and characteristics of Rossby wave packets using a feature-based tracking technique. Mon. Wea. Rev., 142, 35283548, doi:10.1175/MWR-D-13-00371.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Swinbank, R., and et al. , 2016: The TIGGE project and its achievements. Bull. Amer. Meteor. Soc., 97, 4967, doi:10.1175/BAMS-D-13-00191.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Teubler, F., and M. Riemer, 2016: Dynamics of Rossby wave packets in a quantitative potential vorticity–potential temperature framework. J. Atmos. Sci., 73, 10631081, doi:10.1175/JAS-D-15-0162.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Torn, R. D., 2010a: Diagnosis of the downstream ridging associated with extratropical transition using short-term ensemble forecasts. J. Atmos. Sci., 67, 817833, doi:10.1175/2009JAS3093.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Torn, R. D., 2010b: Ensemble-based sensitivity analysis applied to African easterly waves. Wea. Forecasting, 25, 6178, doi:10.1175/2009WAF2222255.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Torn, R. D., and G. J. Hakim, 2008: Ensemble-based sensitivity analysis. Mon. Wea. Rev., 136, 663677, doi:10.1175/2007MWR2132.1.

  • Torn, R. D., and G. J. Hakim, 2009: Initial condition sensitivity of western Pacific extratropical transitions determined using ensemble-based sensitivity analysis. Mon. Wea. Rev., 137, 33883406, doi:10.1175/2009MWR2879.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Torn, R. D., and D. Cook, 2013: The role of vortex and environment errors in genesis forecasts of Hurricanes Danielle and Karl (2010). Mon. Wea. Rev., 141, 232251, doi:10.1175/MWR-D-12-00086.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Torn, R. D., and G. J. Hakim, 2015: Comparison of wave packets associated with extratropical transition and winter cyclones. Mon. Wea. Rev., 143, 17821803, doi:10.1175/MWR-D-14-00006.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zheng, M., E. K. M. Chang, and B. A. Colle, 2013: Ensemble sensitivity tools for assessing extratropical cyclone intensity and track predictability. Wea. Forecasting, 28, 11331156, doi:10.1175/WAF-D-12-00132.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
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Amplification of the Downstream Wave Train during Extratropical Transition: Sensitivity Studies

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  • 1 Deutscher Wetterdienst, Research and Development, Numerical Models, Offenbach, Germany
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Abstract

A tropical cyclone (TC) undergoing extratropical transition (ET) may support the amplification of a Rossby wave train in the downstream midlatitudes. Within the context of downstream baroclinic development, the TC acts as an additional source of eddy kinetic energy (). Previous studies concluded that the impact depends, in particular, on the phasing between the TC and the midlatitude flow and the continuation of the generation during ET. These studies did not quantify the impact of ET on the within a downstream Rossby wave train.

The present study uses ensemble sensitivity analysis to examine the sensitivity of downstream Rossby wave train amplification to the budget of the transitioning TC and of the upstream midlatitude features for Typhoon Choi-Wan (2009) and Hurricane Hanna (2008) in ECMWF ensemble forecasts. The amplification of the downstream wave train is measured using the amplitude of its associated maxima. The sensitivity of the maximum’s intensity at a particular forecast time to the budget terms of the TC and the upstream midlatitudes at earlier forecast times is determined. The results show that increasing the budget terms within Choi-Wan (Hanna) by one standard deviation can result in an up to 36% (23%) more intense downstream maximum. This is favored by the phasing between Choi-Wan and the midlatitude trough, and the reintensification of Hanna, respectively. By contrast, weaker contributions to downstream Rossby wave amplification arise from budget terms associated with flow features in the upstream midlatitudes.

Current affiliation: World Meteorological Organization, Geneva, Switzerland.

© 2017 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author e-mail: Julia Keller, j.h.keller@web.de

This article is included in the Predictability and Dynamics of Weather Systems in the Atlantic-European Sector (PANDOWAE) Special Collection.

Abstract

A tropical cyclone (TC) undergoing extratropical transition (ET) may support the amplification of a Rossby wave train in the downstream midlatitudes. Within the context of downstream baroclinic development, the TC acts as an additional source of eddy kinetic energy (). Previous studies concluded that the impact depends, in particular, on the phasing between the TC and the midlatitude flow and the continuation of the generation during ET. These studies did not quantify the impact of ET on the within a downstream Rossby wave train.

The present study uses ensemble sensitivity analysis to examine the sensitivity of downstream Rossby wave train amplification to the budget of the transitioning TC and of the upstream midlatitude features for Typhoon Choi-Wan (2009) and Hurricane Hanna (2008) in ECMWF ensemble forecasts. The amplification of the downstream wave train is measured using the amplitude of its associated maxima. The sensitivity of the maximum’s intensity at a particular forecast time to the budget terms of the TC and the upstream midlatitudes at earlier forecast times is determined. The results show that increasing the budget terms within Choi-Wan (Hanna) by one standard deviation can result in an up to 36% (23%) more intense downstream maximum. This is favored by the phasing between Choi-Wan and the midlatitude trough, and the reintensification of Hanna, respectively. By contrast, weaker contributions to downstream Rossby wave amplification arise from budget terms associated with flow features in the upstream midlatitudes.

Current affiliation: World Meteorological Organization, Geneva, Switzerland.

© 2017 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author e-mail: Julia Keller, j.h.keller@web.de

This article is included in the Predictability and Dynamics of Weather Systems in the Atlantic-European Sector (PANDOWAE) Special Collection.

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