• Agudelo, P. A., , C. D. Hoyos, , J. A. Curry, , and P. J. Webster, 2011: Probabilistic discrimination between large-scale environments of intensifying and decaying African easterly waves. Climate Dyn., 36, 13791401.

    • Search Google Scholar
    • Export Citation
  • Arnault, J., , and F. Roux, 2010: Comparison between two case studies of developing and nondeveloping African easterly waves during NAMMA and AMM/SOP-3: Absolute vertical vorticity budget. Mon. Wea. Rev., 138, 14201445.

    • Search Google Scholar
    • Export Citation
  • Arnault, J., , and F. Roux, 2011: Characteristics of African easterly waves associated with tropical cyclogenesis in the Cape Verde Islands region in July–August–September of 2004–2008. Atmos. Res., 100, 6182.

    • Search Google Scholar
    • Export Citation
  • Avila, L. A., 1991: Eastern North Pacific hurricane season of 1990. Mon. Wea. Rev., 119, 20342046.

  • Avila, L. A., , and R. J. Pasch, 1992: Atlantic tropical systems of 1991. Mon. Wea. Rev., 120, 26882696.

  • Awaka, J., , T. Iguchi, , and K. Okamoto, 1998: Early results on rain type classification by the Tropical Rainfall Measuring Mission (TRMM) precipitation radar. Proc. Eighth URSI Commission F. Triennial Open Symp., Aveiro, Portugal, International Union of Radio Science, 143–146.

  • Awaka, J., , T. Iguchi, , and K. Okamoto, 2009: TRMM PR standard algorithm 2A23 and its performance on bright band detection. J. Meteor. Soc. Japan, 87A, 3152.

    • Search Google Scholar
    • Export Citation
  • Bister, M., , and K. A. Emanuel, 1997: The genesis of Hurricane Guillermo: TEXMEX analyses and a modeling study. Mon. Wea. Rev., 125, 26622682.

    • Search Google Scholar
    • Export Citation
  • Boccippio, D. J., , S. J. Goodman, , and S. Heckman, 2000: Regional differences in tropical lightning distributions. J. Appl. Meteor., 39, 22312248.

    • Search Google Scholar
    • Export Citation
  • Boccippio, D. J., , W. J. Koshak, , and R. J. Blakeslee, 2002: Performance assessment of the optical transient detector and lightning imaging sensor. Part I: Predicted diurnal variability. J. Atmos. Oceanic Technol., 19, 13181332.

    • Search Google Scholar
    • Export Citation
  • Bolton, D., 1980: The computation of equivalent potential temperature. Mon. Wea. Rev., 108, 10461053.

  • Cecil, D. J., , and E. J. Zipser, 1999: Relationships between tropical cyclone intensity and satellite-based indicators of inner core convection: 85-GHz ice-scattering signature and lightning. Mon. Wea. Rev., 127, 103123.

    • Search Google Scholar
    • Export Citation
  • Christian, H. J., , R. J. Blakeslee, , and S. L. Goodman, 1992: Lightning Imaging Sensor (LIS) for the Earth Observing System. NASA TM-4350, 36 pp.

  • Christian, H. J., and Coauthors, 2003: Global frequency and distribution of lightning as observed from space by the optical transient detector. J. Geophys. Res., 108, 4005, doi:10.1029/2002JD002347.

    • Search Google Scholar
    • Export Citation
  • Chronis, T. G., , E. R. Williams, , E. N. Anagnostou, , and W. A. Petersen, 2007: African lightning: Indicator of tropical Atlantic cyclone formation. Eos, Trans. Amer. Geophys. Union, 88, 397398.

    • Search Google Scholar
    • Export Citation
  • Deierling, W., , and W. A. Petersen, 2008: Total lightning activity as an indicator of updraft characteristics. J. Geophys. Res., 113, D16210, doi:10.1029/2007JD009598.

    • 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.

    • Search Google Scholar
    • Export Citation
  • Emanuel, K. A., 1989: The finite-amplitude nature of tropical cyclogenesis. J. Atmos. Sci., 46, 34313456.

  • Gray, W. M., 1968: Global view of the origin of tropical disturbances and storms. Mon. Wea. Rev., 96, 669700.

  • Hendricks, E. A., , M. T. Montgomery, , and C. A. Davis, 2004: The role of “vortical” hot towers in the formation of tropical cyclone Diana (1984). J. Atmos. Sci., 61, 12091232.

    • Search Google Scholar
    • Export Citation
  • Hopsch, S. B., , C. D. Thorncroft, , and K. R. Tyle, 2010: Analysis of African easterly wave structures and their role in influencing tropical cyclogenesis. Mon. Wea. Rev., 138, 13991419.

    • Search Google Scholar
    • Export Citation
  • Houze, R. A., Jr., 1989: Observed structure of mesoscale convective systems and implications for large-scale heating. Quart. J. Roy. Meteor. Soc., 115, 425461.

    • Search Google Scholar
    • Export Citation
  • Houze, R. A., Jr., , W.-C. Lee, , and M. M. Bell, 2009: Convective contribution to the genesis of Hurricane Ophelia (2005). Mon. Wea. Rev., 137, 27782800.

    • Search Google Scholar
    • Export Citation
  • Iguchi, T., , T. Kozu, , R. Meneghini, , J. Awaka, , and K. Okamoto, 2000: Rain-profiling algorithm for the TRMM precipitation radar. J. Appl. Meteor., 39, 20382052.

    • Search Google Scholar
    • Export Citation
  • Iguchi, T., , T. Kozu, , J. Kwiatkowski, , R. Meneghini, , J. Awaka, , and K. Okamoto, 2009: Uncertainties in the rain profiling algorithm for the TRMM precipitation radar. J. Meteor. Soc. Japan, 87A, 130.

    • Search Google Scholar
    • Export Citation
  • Kalnay, E., and Coauthors, 1996: The NCEP/NCAR 40-Year Reanalysis Project. Bull. Amer. Meteor. Soc., 77, 437471.

  • Kiladis, G. N., , C. D. Thorncroft, , and N. M. J. Hall, 2006: Three-dimensional structure and dynamics of African easterly waves. Part I: Observations. J. Atmos. Sci., 63, 22122230.

    • Search Google Scholar
    • Export Citation
  • Kozu, T., and Coauthors, 2001: Development of precipitation radar onboard the Tropical Rainfall Measuring Mission (TRMM) satellite. IEEE Trans. Geosci. Remote Sens., 39, 102116.

    • Search Google Scholar
    • Export Citation
  • Kummerow, C., , W. Barnes, , T. Kozu, , J. Shiue, , and J. Simpson, 1998: The Tropical Rainfall Measuring Mission (TRMM) sensor package. J. Atmos. Oceanic Technol., 15, 809817.

    • Search Google Scholar
    • Export Citation
  • Kurihara, Y., , and R. E. Tuleya, 1981: A numerical simulation study on the genesis of a tropical storm. Mon. Wea. Rev., 109, 16291653.

    • Search Google Scholar
    • Export Citation
  • Landsea, C. W., 1993: A climatology of intense (or major) Atlantic hurricanes. Mon. Wea. Rev., 121, 17031713.

  • Landsea, C. W., , G. D. Bell, , W. M. Gray, , and S. B. Goldenberg, 1998: The extremely active 1995 Atlantic hurricane season: Environmental conditions and verification of seasonal forecasts. Mon. Wea. Rev., 126, 11741193.

    • Search Google Scholar
    • Export Citation
  • Leppert, K. D., II, , and W. A. Petersen, 2010: Electrically active hot towers in African easterly waves prior to tropical cyclogenesis. Mon. Wea. Rev., 138, 663687.

    • Search Google Scholar
    • Export Citation
  • Leppert, K. D., II, , W. A. Petersen, , and D. J. Cecil, 2013: Electrically active convection in tropical easterly waves and implications for tropical cyclogenesis in the Atlantic and east Pacific. Mon. Wea. Rev., 141, 542–556.

    • Search Google Scholar
    • Export Citation
  • Liu, Z., , D. Ostrenga, , G. G. Leptoukh, , and A. V. Mehta, 2009: Online visualization and analysis of global half-hourly pixel-resolution infrared dataset. Extended Abstracts, 25th Conf. on Int. Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology, Phoenix, AZ, Amer. Meteor. Soc., J3.4. [Available online at https://ams.confex.com/ams/89annual/webprogram/Paper148189.html.]

  • McBride, J. L., , and R. Zehr, 1981: Observational analysis of tropical cyclone formation. Part II: Comparison of non-developing versus developing systems. J. Atmos. Sci., 38, 11321151.

    • Search Google Scholar
    • Export Citation
  • Meneghini, R., , T. Iguchi, , T. Kozu, , L. Liao, , K. Okamoto, , J. A. Jones, , and J. Kwiatkowski, 2000: Use of the surface reference technique for path attenuation estimates from the TRMM precipitation radar. J. Appl. Meteor., 39, 20532070.

    • Search Google Scholar
    • Export Citation
  • Molinari, J., , and D. Vollaro, 2000: Planetary- and synoptic-scale influences on eastern Pacific tropical cyclogenesis. Mon. Wea. Rev., 128, 32963307.

    • Search Google Scholar
    • Export Citation
  • Montgomery, M. T., , M. E. Nicholls, , T. A. Cram, , and A. B. Saunders, 2006: A vortical hot tower route to tropical cyclogenesis. J. Atmos. Sci., 63, 355386.

    • Search Google Scholar
    • Export Citation
  • National Hurricane Center, cited 2011: NHC data archive of hurricane seasons. [Available online at http://www.nhc.noaa.gov/pastall.shtml.]

  • Nolan, D. S., 2007: What is the trigger for tropical cyclogenesis? Aust. Meteor. Mag., 56, 241266.

  • Panofsky, H. A., , and G. W. Brier, 1958: Some Applications of Statistics to Meteorology. Pennsylvania State University, 224 pp.

  • Price, C., , Y. Yair, , and M. Asfur, 2007: East African lightning as a precursor of Atlantic hurricane activity. Geophys. Res. Lett., 34, L09805, doi:10.1029/2006GL028884.

    • Search Google Scholar
    • Export Citation
  • Raymond, D. J., , S. L. Sessions, , and C. Lopez Carrillo, 2011: Thermodynamics of tropical cyclogenesis in the northwest Pacific. J. Geophys. Res., 116, D18101, doi:10.1029/2011JD015624.

    • Search Google Scholar
    • Export Citation
  • Rotunno, R., , and K. A. Emanuel, 1987: An air–sea interaction theory for tropical cyclones. Part II: Evolutionary study using a non-hydrostatic axisymmetric numerical model. J. Atmos. Sci., 44, 542561.

    • Search Google Scholar
    • Export Citation
  • Rutledge, S. A., , E. R. Williams, , and T. D. Keenan, 1992: The Down Under Doppler and Electricity Experiment (DUNDEE): Overview and preliminary results. Bull. Amer. Meteor. Soc., 73, 316.

    • Search Google Scholar
    • Export Citation
  • Saunders, C. P. R., , and S. L. Peck, 1998: Laboratory studies of the influence of the rime accretion rate on charge transfer during crystal/graupel collisions. J. Geophys. Res., 103 (D12), 13 94913 956.

    • Search Google Scholar
    • Export Citation
  • Shapiro, L. J., , and H. E. Willoughby, 1982: The response of balanced hurricanes to local sources of heat and momentum. J. Atmos. Sci., 39, 378394.

    • Search Google Scholar
    • Export Citation
  • Smith, E. A., , H. J. Cooper, , X. Xiang, , A. Mugnai, , and G. J. Tripoli, 1992: Foundations for statistical–physical precipitation retrieval from passive microwave satellite measurements. Part I: Brightness temperature properties of a time-dependent cloud-radiation model. J. Appl. Meteor., 31, 506531.

    • Search Google Scholar
    • Export Citation
  • Spencer, R. W., , H. M. Goodman, , and R. E. Hood, 1989: Precipitation retrieval over land and ocean with the SSM/I: Identification and characteristics of the scattering signal. J. Atmos. Oceanic Technol., 6, 254273.

    • Search Google Scholar
    • Export Citation
  • Takahashi, T., 1978: Riming electrification as a charge generation mechanism in thunderstorms. J. Atmos. Sci., 35, 15361548.

  • Toracinta, E. R., , D. J. Cecil, , E. J. Zipser, , and S. W. Nesbitt, 2002: Radar, passive microwave, and lightning characteristics of precipitating systems in the tropics. Mon. Wea. Rev., 130, 802824.

    • Search Google Scholar
    • Export Citation
  • Trier, S. B., , W. C. Skamarock, , and M. A. LeMone, 1997: Structure and evolution of the 22 February 1993 TOGA COARE squall line: Organization mechanisms inferred from numerical simulation. J. Atmos. Sci., 54, 386407.

    • Search Google Scholar
    • Export Citation
  • Williams, E. R., , S. A. Rutledge, , S. G. Geotis, , N. Renno, , E. Rasmussen, , and T. Rickenbach, 1992: A radar and electrical study of tropical “hot towers.” J. Atmos. Sci., 49, 13861395.

    • Search Google Scholar
    • Export Citation
  • Zipser, E. J., 1994: Deep cumulonimbus cloud systems in the tropics with and without lightning. Mon. Wea. Rev., 122, 18371851.

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Relation between Tropical Easterly Waves, Convection, and Tropical Cyclogenesis: A Lagrangian Perspective

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  • 1 University of Alabama in Huntsville, Huntsville, Alabama,
  • | 2 NASA Goddard Space Flight Center/Wallops Flight Facility, Wallops Island, Virginia
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Abstract

In this study, a wave-following Lagrangian framework was used to examine the evolution of tropical easterly wave structure, circulation, and convection in the days leading up to and including tropical cyclogenesis in the Atlantic and east Pacific basins. After easterly waves were separated into northerly, southerly, trough, and ridge phases using the National Centers for Environmental Prediction–National Center for Atmospheric Research reanalysis 700-hPa meridional wind, waves that developed a tropical cyclone [developing waves (DWs)] and waves that never developed a cyclone [nondeveloping waves (NDWs)] were identified. Day zero (D0) was defined as the day on which a tropical depression was identified for DWs or the day the waves achieved maximum 850-hPa vorticity for NDWs. Both waves types were then traced from five days prior to D0 (D − 5) through one day after D0. Results suggest that as genesis is approached for DWs, the coverage by convection and cold cloudiness (e.g., fractional coverage by infrared brightness temperatures ≤240 K) increases, while convective intensity (e.g., lightning flash rate) decreases. Therefore, the coverage by convection appears to be more important than the intensity of convection for tropical cyclogenesis. In contrast, convective coverage and intensity both increase from D − 5 to D0 for NDWs. Compared to NDWs, DWs are associated with significantly greater coverage by cold cloudiness, large-scale moisture throughout a deep layer, and large-scale, upper-level (~200 hPa) divergence, especially within the trough and southerly phases, suggesting that these parameters are most important for cyclogenesis and for distinguishing DWs from NDWs.

Current affiliation: NASA Marshall Space Flight Center, Huntsville, Alabama.

Corresponding author address: Kenneth Leppert II, NSSTC, 320 Sparkman Dr., Rm. 4074, Huntsville, AL 35805. E-mail: leppert@nsstc.uah.edu

Abstract

In this study, a wave-following Lagrangian framework was used to examine the evolution of tropical easterly wave structure, circulation, and convection in the days leading up to and including tropical cyclogenesis in the Atlantic and east Pacific basins. After easterly waves were separated into northerly, southerly, trough, and ridge phases using the National Centers for Environmental Prediction–National Center for Atmospheric Research reanalysis 700-hPa meridional wind, waves that developed a tropical cyclone [developing waves (DWs)] and waves that never developed a cyclone [nondeveloping waves (NDWs)] were identified. Day zero (D0) was defined as the day on which a tropical depression was identified for DWs or the day the waves achieved maximum 850-hPa vorticity for NDWs. Both waves types were then traced from five days prior to D0 (D − 5) through one day after D0. Results suggest that as genesis is approached for DWs, the coverage by convection and cold cloudiness (e.g., fractional coverage by infrared brightness temperatures ≤240 K) increases, while convective intensity (e.g., lightning flash rate) decreases. Therefore, the coverage by convection appears to be more important than the intensity of convection for tropical cyclogenesis. In contrast, convective coverage and intensity both increase from D − 5 to D0 for NDWs. Compared to NDWs, DWs are associated with significantly greater coverage by cold cloudiness, large-scale moisture throughout a deep layer, and large-scale, upper-level (~200 hPa) divergence, especially within the trough and southerly phases, suggesting that these parameters are most important for cyclogenesis and for distinguishing DWs from NDWs.

Current affiliation: NASA Marshall Space Flight Center, Huntsville, Alabama.

Corresponding author address: Kenneth Leppert II, NSSTC, 320 Sparkman Dr., Rm. 4074, Huntsville, AL 35805. E-mail: leppert@nsstc.uah.edu
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