Abstract
Extending the lead time of precipitation nowcasts is vital to improvements in heavy rainfall warning, flood mitigation, and water resource management. Because the TREC vector (tracking radar echo by correlation) represents only the instantaneous trend of precipitation echo motion, the approach using derived echo motion vectors to extrapolate radar reflectivity as a rainfall forecast is not satisfactory if the lead time is beyond 30 minutes. For longer lead times, the effect of ambient winds on echo movement should be considered. In this paper, an extrapolation algorithm that extends forecast lead times up to 3 hours was developed to blend TREC vectors with model-predicted winds. The TREC vectors were derived from radar reflectivity patterns in 3 km height CAPPI (constant altitude plan position indicator) mosaics through a cross-correlation technique. The background steering winds were provided by predictions of the rapid update assimilation model CHAF (cycle of hourly assimilation and forecast). A similarity index was designed to determine the vertical level at which model winds were applied in the extrapolation process, which occurs via a comparison between model winds and radar vectors. Based on a summer rainfall case study, it is found that the new algorithm provides a better forecast.
Similar content being viewed by others
References
Akima, H., 1978: A method of bivariate interpolation and smooth surface fitting for irregularly distributed data points. ACM Transactions on Mathematical Software (TOMS), 4(2), 148–159.
Benjamin, S. G., and Coauthors, 2004: An hourly assimilation-forecast cycle: The RUC. Mon. Wea. Rev., 132, 495–518.
Berenguer, M., C. Corral, R. Sanchez-Diezma, and D. Sempere-Torres, 2005: Hydrological validation of a radar-based nowcasting technique. Journal of Hydrometeorology, 6, 532–549.
Chen, D. H., and X. S. Shen, 2006: Recent progress on GRAPES research and application. Journal of Applied Meteorological Science, 17(6), 773–777. (in Chinese)
Chen, M., and X.-Y. Huang, 2006: Digital filter initialization for MM5. Mon. Wea. Rev., 134, 1222–1236.
Chester, W. N., and C. F. James, 1975: Movement and propagation of multicellular convective storms. Pure and Applied Geophysics, 113(??), 747–764.
Corfidi, S. F, J. M. Fritsch, and J. H. Merritt, 1996: Predicting the movement of mesoscale convective complexes. Weather Forecasting, 11, 41–46.
Dixon, M., and G. Wiener, 1993: TITAN: Thunderstorm identification, tracking, and nowcasting—A radar-based methodology. J. Atmos. Oceanic Technol., 10, 785–797.
Feng, W., Q. L. Wan, Z. T. Chen, W. Y. Ding, and Y. Y. Huang, 2008: Hourly assimilation of cloud motion winds and its impact on torrential rain forecast. Acta Meteorologica Sinica, 66(4), 500–512. (in Chinese)
Feng, Y., and D. H. Kitzmiller, 2006: A short-range quantitative precipitation forecast algorithm using back-propagation neural network approach. Adv. Atmos. Sci., 23(3), 405–414, doi: 10.1007/s00376-006-0405-7.
Germann, U., and I. Zawadzki, 2002: Scale-dependence of the predictability of precipitation from continental radar images. Part I: Description of the methodology. Mon. Wea. Rev., 130, 2859–2873.
Kessinger, C., S. Ellis, and J. Van Andel, 2003: The radar echo classifier: A fuzzy logic algorithm for the WSR 88D. 3rd Conference on Artificial Intelligence Applications to the Environmental Science, Amer. Meteor. Soc., 9–13 Feb., Long Beach, CA.
Johnson, J. T., P. L. MacKeen, A. Witt, E. D. Mitchell, G.. J. Stumpf, M. D. Eilts, and K. W. Thomas, 1998: The storm cell identification and tracking algorithm: an enhanced WSR-88D algorithm. Wea. Forecasting, 13, 263–276.
Li, L., and W. Schmid, 1995: Nowcasting of motion and growth of precipitation with radar over a complex orography. J. Appl. Meteor., 34, 1286–1300.
Li, P. W., and E. S. T. Lai., 2004: Applications of radar-based nowcasting techniques for mesoscale weather forecasting in Hong Kong. Meteorological Applications, 11(3), 253–264. (in Chinese)
Liang, K., Q. L. Wan, W. Y. Ding, Z. T. Chen, and Y. Y. Huang, 2007: The application of assimilated aircraft data in simulating a heavy rain over South China in June 2005. Journal of Tropical Meteorology, 13(2), 160–164.
Lynch, P., and X.-Y. Huang, 1992: Initialization of the HIRLAM model using a digital filter. Mon. Wea. Rev., 120, 1019–1034.
Marc, R. G., R. P. Lowther, and S. F. Corfidi, 2006: Forecasting mesoscale convective complex movement in Central South America. National Weather Digest, 30, 68–76.
Mecklenburg, S., J. Joss, and W. Schmid, 2000: Improving the nowcasting of precipitation in an Alpine region with an enhanced radar echo tracking algorithm. J. Hydrol., 239, 46–68.
Novák, P., J. Walder, and J. Kráčmar, 2002: The first attempts at the radar echo prediction in the Czech weather radar network. Proceedings of ERAD (European Conference on Radar meteorology), 55–58.
Novák P., 2007: The Czech Hydrometeorological Institute’s severe storm nowcasting. Atmos. Res., 83, 450–457.
Rinehar, R. E., and E. T. Garvey, 1978: Three-dimensional storm motion detection by conventional weather radar. Nature, 273, 287–289.
Tuttle, J. D., and G. B. Foote, 1990: Determination of boundary layer airflow from a single Doppler radar. J. Atmos. Oceanic Technol., 7, 218–232.
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.
Winterrath, T., and W. Rosenow, 2007: A new module for the tracking of radar-derived precipitation with model-derived winds. Advances in Geosciences, 10, 77–83.
Zgonc, A., and J. Rakovec, 1998: Time extrapolation of radar echo patterns. Preprints, COST (Cooperation in Science and Technology) -75 Final Seminar “Advanced Weather Radar Systems”. Locarno, Switzerland, Ed. C.G. Collier, European Commission, EUR 18567 EN, 229–238.
Zhang, C. Z., Q. L. Wan, Y. Y. Huang, Z. T. Chen, and W. Y. Ding, 2008: Numerical experiments on the impact of initial conditions upon precipitation in warn region over south of China, Journal of Tropical Meteorology, 24(6), 576–589. (in Chinese)
Zhang, H., J. S. Xue, S. Y. Zhuang, G. F. Zhu, and Z. C. Zhu, 2004: Idea experiments of GRAPES three-dimensional variational data assimilation system. Acta Meteorologica Sinica, 62(??), 31–41. (in Chinese)
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Liang, Q., Feng, Y., Deng, W. et al. A composite approach of radar echo extrapolation based on TREC vectors in combination with model-predicted winds. Adv. Atmos. Sci. 27, 1119–1130 (2010). https://doi.org/10.1007/s00376-009-9093-4
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00376-009-9093-4