Snow Nowcasting Using a Real-Time Correlation of Radar Reflectivity with Snow Gauge Accumulation

Roy Rasmussen National Center for Atmospheric Research, Boulder, Colorado

Search for other papers by Roy Rasmussen in
Current site
Google Scholar
PubMed
Close
,
Michael Dixon National Center for Atmospheric Research, Boulder, Colorado

Search for other papers by Michael Dixon in
Current site
Google Scholar
PubMed
Close
,
Steve Vasiloff National Severe Storms Laboratory, Norman, Oklahoma

Search for other papers by Steve Vasiloff in
Current site
Google Scholar
PubMed
Close
,
Frank Hage National Center for Atmospheric Research, Boulder, Colorado

Search for other papers by Frank Hage in
Current site
Google Scholar
PubMed
Close
,
Shelly Knight National Center for Atmospheric Research, Boulder, Colorado

Search for other papers by Shelly Knight in
Current site
Google Scholar
PubMed
Close
,
J. Vivekanandan National Center for Atmospheric Research, Boulder, Colorado

Search for other papers by J. Vivekanandan in
Current site
Google Scholar
PubMed
Close
, and
Mei Xu National Center for Atmospheric Research, Boulder, Colorado

Search for other papers by Mei Xu in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

This paper describes and evaluates an algorithm for nowcasting snow water equivalent (SWE) at a point on the surface based on a real-time correlation of equivalent radar reflectivity (Ze) with snow gauge rate (S). It is shown from both theory and previous results that ZeS relationships vary significantly during a storm and from storm to storm, requiring a real-time correlation of Ze and S. A key element of the algorithm is taking into account snow drift and distance of the radar volume from the snow gauge. The algorithm was applied to a number of New York City snowstorms and was shown to have skill in nowcasting SWE out to at least 1 h when compared with persistence. The algorithm is currently being used in a real-time winter weather nowcasting system, called Weather Support to Deicing Decision Making (WSDDM), to improve decision making regarding the deicing of aircraft and runway clearing. The algorithm can also be used to provide a real-time ZS relationship for Weather Surveillance Radar-1988 Doppler (WSR-88D) if a well-shielded snow gauge is available to measure real-time SWE rate and appropriate range corrections are made.

Corresponding author address: Dr. Roy Rasmussen, NCAR, P.O. Box 3000, Boulder, CO 80307. rasmus@ucar.edu

Abstract

This paper describes and evaluates an algorithm for nowcasting snow water equivalent (SWE) at a point on the surface based on a real-time correlation of equivalent radar reflectivity (Ze) with snow gauge rate (S). It is shown from both theory and previous results that ZeS relationships vary significantly during a storm and from storm to storm, requiring a real-time correlation of Ze and S. A key element of the algorithm is taking into account snow drift and distance of the radar volume from the snow gauge. The algorithm was applied to a number of New York City snowstorms and was shown to have skill in nowcasting SWE out to at least 1 h when compared with persistence. The algorithm is currently being used in a real-time winter weather nowcasting system, called Weather Support to Deicing Decision Making (WSDDM), to improve decision making regarding the deicing of aircraft and runway clearing. The algorithm can also be used to provide a real-time ZS relationship for Weather Surveillance Radar-1988 Doppler (WSR-88D) if a well-shielded snow gauge is available to measure real-time SWE rate and appropriate range corrections are made.

Corresponding author address: Dr. Roy Rasmussen, NCAR, P.O. Box 3000, Boulder, CO 80307. rasmus@ucar.edu

Save
  • Battan, J. L. 1973. Radar Observation of the Atmosphere. The University of Chicago Press, 324 pp.

  • Bernadin, S., C. Bubuisson, and J-L. Laforte. 1997. Development of laboratory test procedures to replace field anti-icing fluid tests (snow equivalence tests). Rep. TP13141E, Transportation Development Centre, Safety and Security, Transport Canada, 109 pp.

    • Search Google Scholar
    • Export Citation
  • Bohren, C. F. and L. J. Battan. 1980. Radar backscattering by inhomogenous precipitation particles. J. Atmos. Sci. 37:18211827.

  • Boucher, R. J. and J. G. Weiler. 1985. Radar determination of snowfall rate and accumulation. J. Climate Appl. Meteor. 24:6873.

  • Braham, R. R. 1990. Snow particle size spectra in lake effect snows. J. Appl. Meteor. 29:200207.

  • Carlson, P. E. and J. S. Marshall. 1972. Measurement of snowfall by radar. J. Appl. Meteor. 11:494500.

  • Collier, C. G. and P. R. Larke. 1978. A case study of the measurement of snowfall by radar: An assessment of accuracy. Quart. J. Roy. Meteor. Soc. 104:615621.

    • Search Google Scholar
    • Export Citation
  • Debye, P. 1929. Polar Molecules. Chemical Catalogue Co.

  • Donaldson, R. J., R. M. Dyer, and M. J. Kraus. 1975. An objective evaluation of techniques for predicting severe weather events. Preprints, Ninth Conf. on Severe Local Storms, Norman, OK, Amer. Meteor. Soc., 321–326.

    • Search Google Scholar
    • Export Citation
  • Fujiyoshi, Y., T. Endoh, T. Yamada, K. Tsuboki, Y. Tachibana, and G. Wakahama. 1990. Determination of a ZR relationship for snowfall using a radar and sensitive snow gauges. J. Appl. Meteor. 29:147152.

    • Search Google Scholar
    • Export Citation
  • Fulton, R. A., J. P. Breidenbach, D-J. Seo, D. A. Miller, and T. O'Bannon. 1998. The WSR-88D rainfall algorithm. Wea. Forecasting 13:377395.

    • Search Google Scholar
    • Export Citation
  • Goodison, B. E. 1978. Accuracy of Canadian snow gage measurements. J. Appl. Meteor. 17:15421548.

  • Gray, D. M. and D. H. Male. 1981. Handbook of Snow: Principles, Processes, Management and Use. Pergamon Press, 776 pp.

  • Gunn, K. L. S. and J. S. Marshall. 1958. The distribution with size of aggregate snowflakes. J. Meteor. 15:452461.

  • Hariyama, T. 1978. Observation of size distribution of graupel and snow flake. J. Fac. Sci., Hokkaido Univ., Ser. 7 5 3:6777.

  • Imai, J. 1960. Raindrop size distributions and the ZR relationship. Proc. Eighth Weather Radar Conf., Boston, MA, Amer. Meteor. Soc., 321–326.

    • Search Google Scholar
    • Export Citation
  • Langville, R. C. and R. S. Thain. 1951. Some quantitative measurements of three-centimeter radar echoes from falling snow. Can. J. Phys. 29:482490.

    • Search Google Scholar
    • Export Citation
  • Marshall, J. S. and K. L. S. Gunn. 1952. Measurement of snow parameters by radar. J. Meteor. 9:322327.

  • Ohtake, T. and T. Henmi. 1970. Radar reflectivity of aggregated snowflakes. Preprints, 14th Conf. on Radar Meteorology, Tucson, AZ, Amer. Meteor. Soc., 209–210.

    • Search Google Scholar
    • Export Citation
  • Passarelli Jr., R. E. 1978. A theoretical explanation for ZR relationships in snow. Preprints, 18th Conf. on Radar Meteorology, Atlanta, GA, Amer. Meteor. Soc., 332–335.

    • Search Google Scholar
    • Export Citation
  • Puhakka, T. 1975. On the dependence of the ZR relation on the temperature in snowfall. Preprints, 16th Conf. on Radar Meteorology, Houston, TX, Amer. Meteor. Soc., 504–507.

    • Search Google Scholar
    • Export Citation
  • Rasmussen, R. M., A. Hills, S. Landolt, and C. Knight. 1999a. Results of holdover time testing of type IV anti-icing fluids with the improved NCAR artificial snow generation system. Rep. DOT/FAA/AR-99/10, U.S. Dept. of Transportation, Federal Aviation Administration, 36 pp.

    • Search Google Scholar
    • Export Citation
  • Rasmussen, R. M., J. Vivekanandan, J. Cole, B. Myers, and C. Masters. 1999b. The estimation of snowfall rate using visibility. J. Appl. Meteor. 38:15421563.

    • Search Google Scholar
    • Export Citation
  • Rasmussen, R. M. Coauthors,. 2001. Weather Support to Deicing Decision Making (WSDDM): A winter weather nowcasting system. Bull. Amer. Meteor. Soc. 82:579595.

    • Search Google Scholar
    • Export Citation
  • Rinehart, R. E. and E. T. Garvey. 1978. Three-dimensional storm motion detection by conventional weather radar. Nature 273:287289.

  • Rogers, D. 1974. The aggregation of natural ice crystals. Rep. AR110m, 91 pp. [Available from Department of Atmospheric Sciences, College of Engineering, University of Wyoming, Laramie, WY 82072.].

    • Search Google Scholar
    • Export Citation
  • Sekhon, R. S. and R. C. Srivastava. 1970. Snow size spectra and radar reflectivity. J. Atmos. Sci. 27:299307.

  • Sheppard, B. E. 1990. Measurement of raindrop size distributions using a small Doppler radar. J. Atmos. Oceanic Technol. 7:255268.

  • Smith, P. L. 1984. Equivalent radar reflectivity factors for snow and ice particles. J. Climate Appl. Meteor. 23:12581260.

  • Turner, C. M., D. Simms, and R. M. Rasmussen. 1999. Meteorological evaluation of the Weather Support to Deicing Decision Making (WSDDM) system. Preprints, Eighth Conf. on Aviation, Range, and Aerospace Meteorology, Dallas, TX, Amer. Meteor. Soc., 438–442.

    • Search Google Scholar
    • Export Citation
  • Tuttle, J. and B. Foote. 1990. Determination of the boundary layer airflow from a single Doppler radar. J. Atmos. Oceanic Technol. 7:218232.

    • Search Google Scholar
    • Export Citation
  • Wilson, J. W. 1975. Measurement of snowfall by radar during the IFGL. Preprints, 16th Conf. on Radar Meteorology, Houston, TX, Amer. Meteor. Soc., 508–513.

    • Search Google Scholar
    • Export Citation
  • Yang, D., B. E. Goodison, J. R. Metcalfe, V. S. Golubev, R. Bates, T. Pangburn, and C. L. Hanson. 1998. Accuracy of NWS 8″ standard nonrecording precipitation gauge: Results and application of WMO intercomparison. J. Atmos. Oceanic Technol. 15:5467.

    • Search Google Scholar
    • Export Citation
  • Yoshida, T. 1975. The relation between radar reflectivity and snowfall intensity by kerosene-soaked filter paper method (in Japanese). J. Meteor. Res. 27 3:107111.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 631 127 12
PDF Downloads 445 129 10