Simulation of a Midlatitude Convective Storm Initialized with Bistatic Doppler Radar Data

Thibaut Montmerle Department of Atmospheric and Oceanic Sciences, McGill University, Montreal, Quebec, Canada, and J. S. Marshall Weather Observatory, Sainte Anne de Bellevue, Quebec, Canada

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Alain Caya Department of Atmospheric and Oceanic Sciences, McGill University, Montreal, Quebec, Canada, and J. S. Marshall Weather Observatory, Sainte Anne de Bellevue, Quebec, Canada

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Isztar Zawadzki Department of Atmospheric and Oceanic Sciences, McGill University, Montreal, Quebec, Canada, and J. S. Marshall Weather Observatory, Sainte Anne de Bellevue, Quebec, Canada

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Abstract

An analysis is developed to initialize a cloud-resolving model from an explicit structure of a precipitating convective system derived from multiple-Doppler radar observations. The different fields of the model prognostic variables that compose the initial state of the simulation are estimated or retrieved using a 4DVAR assimilation method in which the model is used as a weak constraint using two time level observations. This allows for the retrieval of physical fields consistent with the observations and the equations of the model.

This method is applied on a midlatitude summer storm sampled by the McGill bistatic Doppler radar network that occurred on 2 August 1997. During the 30-min-forward simulation, the model succeeds in representing the observed features of the three main cells that compose the storm in terms of precipitation distribution and evolution of the convective activity. After this period, the model produces less stratiform precipitations. Comparisons with a Lagrangian persistency prediction are performed and show a notable improvement in the short-term forecast.

Corresponding author address: Thibaut Montmerle, Dept. of Atmospheric and Oceanic Sciences, McGill University, 805 Sherbrooke Street West, Montreal, PQ H3A 2K6, Canada. Email: montmerl@cumulus.meteo.mcgill.ca

Abstract

An analysis is developed to initialize a cloud-resolving model from an explicit structure of a precipitating convective system derived from multiple-Doppler radar observations. The different fields of the model prognostic variables that compose the initial state of the simulation are estimated or retrieved using a 4DVAR assimilation method in which the model is used as a weak constraint using two time level observations. This allows for the retrieval of physical fields consistent with the observations and the equations of the model.

This method is applied on a midlatitude summer storm sampled by the McGill bistatic Doppler radar network that occurred on 2 August 1997. During the 30-min-forward simulation, the model succeeds in representing the observed features of the three main cells that compose the storm in terms of precipitation distribution and evolution of the convective activity. After this period, the model produces less stratiform precipitations. Comparisons with a Lagrangian persistency prediction are performed and show a notable improvement in the short-term forecast.

Corresponding author address: Thibaut Montmerle, Dept. of Atmospheric and Oceanic Sciences, McGill University, 805 Sherbrooke Street West, Montreal, PQ H3A 2K6, Canada. Email: montmerl@cumulus.meteo.mcgill.ca

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  • Arakawa, A., 1966: Computational design for long-term numerical integrations of the equations of atmospheric motion. J. Comput. Phys, 1 , 119–143.

    • Search Google Scholar
    • Export Citation
  • Bellon, A., and G. L. Austin, 1978: The evaluation of two years of real-time operation of a short-term precipitation forecasting procedure (SHARP). J. Appl. Meteor, 17 , 1778–1787.

    • Search Google Scholar
    • Export Citation
  • Bielli, S., and F. Roux, 1999: Initialization of a cloud-resolving model with airborne Doppler radar observations of an oceanic tropical convective system. Mon. Wea. Rev, 127 , 1038–1055.

    • Search Google Scholar
    • Export Citation
  • Caya, A., I. Zawadzki, F. Fabry, and S. Laroche, 1999: Assimilation of bistatic radar network data and the near-surface index of refractivity. Preprints, 29th Int. Conf. on Radar Meteorology, Montreal, PQ, Canada, Amer. Meteor. Soc., 37–39.

    • Search Google Scholar
    • Export Citation
  • De Elia, R., and I. Zawadzki, 2000: Sidelobe contamination in bistatic radars. J. Atmos. Oceanic Technol, 17 , 1313–1329.

  • Ducrocq, V., J-P. Lafore, J-L. Redelsperger, and F. Orain, 2000: Initialization of a fine scale model for convective system prediction: A case study. Quart. J. Roy. Meteor. Soc, 126 , 3041–3066.

    • Search Google Scholar
    • Export Citation
  • Fabry, F., C. Frush, I. Zawadzki, and A. Kilambi, 1997: On the extraction of near-surface index of refraction using radar phase measurements from ground targets. J. Atmos. Oceanic Technol, 14 , 978–987.

    • Search Google Scholar
    • Export Citation
  • Gal-Chen, T., 1978: A method for the initialization of the anelastic equations: Implications for matching models with observations. Mon. Wea. Rev, 106 , 587–606.

    • Search Google Scholar
    • Export Citation
  • Hane, C. E., and P. S. Ray, 1985: Pressure and buoyancy fields derived from Doppler radar data in a tornadic thunderstorm. J. Atmos. Sci, 42 , 18–35.

    • Search Google Scholar
    • Export Citation
  • Kessler, E., 1969: On the Distribution and Continuity of Water Substance in Atmospheric Circulations. Meteor. Monogr., No. 32, Amer. Meteor. Soc., 32–84.

    • Search Google Scholar
    • Export Citation
  • Kong, F., and M. K. Yau, 1997: An explicit approach to microphysics in MC2. Atmos.–Ocean, 35 , 257–291.

  • Lafore, J. P., J. L. Redelsperger, and G. Jaubert, 1988: Comparison between a three-dimensional simulation and Doppler radar data of a tropical squall line: Transport of mass, momentum, heat, and moisture. J. Atmos. Sci, 45 , 3483–3500.

    • Search Google Scholar
    • Export Citation
  • Laprise, R., D. Caya, G. Bergeron, and M. Giguere, 1997: The formulation of the André Robert MC2 (Mesoscale Compressible Community) Model. Atmos.–Ocean, 35 , 195–220.

    • Search Google Scholar
    • Export Citation
  • Laroche, S., and I. Zawadzki, 1994: A variational analysis method for retrieval of three-dimensional wind field from single-Doppler radar. J. Atmos. Sci, 51 , 2664–2682.

    • Search Google Scholar
    • Export Citation
  • Laroche, S., and I. Zawadzki, 1995: Retrievals of horizontal winds from single-Doppler clear-air data by methods of cross correlation and variational analysis. J. Atmos. Oceanic Technol, 12 , 721–738.

    • Search Google Scholar
    • Export Citation
  • Lilly, D. K., 1990: Numerical prediction of thunderstorms: Has its time come? Quart. J. Roy. Meteor. Soc, 116 , 779–798.

  • Lin, Y., P. S. Ray, and K. W. Johnson, 1993: Initialization of a modeled convective storm using Doppler radar derived fields. Mon. Wea. Rev, 121 , 2757–2775.

    • Search Google Scholar
    • Export Citation
  • Montmerle, T., J-P. Lafore, and J-L. Redelsperger, 2000: A tropical squall line observed during TOGA COARE: Extended comparisons between simulations and Doppler radar data and the role of mid-level wind shear. Mon. Wea. Rev, 128 , 3709–3730.

    • Search Google Scholar
    • Export Citation
  • Protat, A., and I. Zawadzki, 1999: A variational method for real-time retrieval of three-dimensional wind field from multiple-Doppler bistatic radar network data. J. Atmos. Oceanic Technol, 16 , 432–449.

    • Search Google Scholar
    • Export Citation
  • Protat, A., I. Zawadzki, and A. Caya, 2001: Kinematic and thermodynamic study of a shallow hailstorm sampled by the McGill bistatic multiple-Doppler radar network. J. Atmos. Sci, 58 , 1222–1248.

    • Search Google Scholar
    • Export Citation
  • Sun, J., and N. A. Crook, 1997: Dynamical and microphysical retrieval from Doppler radar observations using a cloud model and its adjoint. Part I: Model development and simulated data experiments. J. Atmos. Sci, 54 , 1642–1661.

    • Search Google Scholar
    • Export Citation
  • Sun, J., and N. A. Crook, 1998: Dynamical and microphysical retrieval from Doppler radar observations using a cloud model and its adjoint. Part II: Retrieval experiments of an observed Florida convective storm. J. Atmos. Sci, 55 , 835–852.

    • Search Google Scholar
    • Export Citation
  • Sun, J., and N. A. Crook, 1999: Real-time boundary layer wind and temperature analysis using WSR-88D observations. Preprints, 29th Int. Conference on Radar Meteorology, Montreal, PQ, Canada, Amer. Meteor. Soc., 44–47.

    • Search Google Scholar
    • Export Citation
  • Tanguay, M., A. Robert, and R. Laprise, 1990: A semi-implicit semi-Lagrangian fully compressible regional forecast model. Mon. Wea. Rev, 118 , 1970–1980.

    • Search Google Scholar
    • Export Citation
  • Trier, S. B., W. C. Skamarock, M. A. LeMone, D. B. Parsons, and D. P. Jorgensen, 1996: Structure and evolution of the 22 February 1993 TOGA COARE squall line: Numerical simulation. J. Atmos. Sci, 53 , 2861–2886.

    • Search Google Scholar
    • Export Citation
  • Wilson, J. W., N. A. Crook, C. K. Mueller, J. Sun, and M. Dixon, 1998: Nowcasting thunderstorms: A status report. Bull. Amer. Meteor. Soc, 79 , 2079–2099.

    • Search Google Scholar
    • Export Citation
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