Using Wind Anomalies to Forecast East Coast Winter Storms

Neil A. Stuart NOAA/National Weather Service, Wakefield, Virginia

Search for other papers by Neil A. Stuart in
Current site
Google Scholar
PubMed
Close
and
Richard H. Grumm NOAA/National Weather Service, State College, Pennsylvania

Search for other papers by Richard H. Grumm in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

Forecasting major winter storms is a critical function for all weather services. Conventional model-derived fields from numerical weather prediction models most frequently utilized by operational forecasters, such as pressure level geopotential height, temperature fields, quantitative precipitation forecasts, and model output statistics, are often insufficient to determine whether a winter storm represents a large departure from normal, or has the potential to produce significant snowfall. This paper presents a method, using normalized departures from climatology, to assist forecasters in identifying long-duration and potentially significant winter storms. The focus of this paper is on anomalous low- and upper-level wind anomalies associated with winter storms along the U.S. east coast.

Observed and forecast low-level (850 hPa) and upper-level (300 and 250 hPa) easterly wind anomalies are compared with a 30-yr (1961–90) reanalysis climatology. Anomalous easterly low-level winds are correlated with enhanced low-level forcing and frontogenesis. Strong low-level winds can also contribute to enhanced precipitation rates. Upper-level winds that are anomalously below normal, represented as easterly wind anomalies, are also correlated with systems that are cut off from the main belt of westerlies, which may result in slower movement of the system, leading to long-duration events. The proposed method of evaluating easterly wind anomalies is shown to assist in identifying potentially slow-moving storms with extended periods of enhanced precipitation.

To illustrate this method, winter storms on 25–26 December 2002 and 2–4 January 2003 will be compared with past historical winter storms. The results suggest that the low- and upper-level wind anomalies in the two recent snowstorms share common characteristics with several record snowstorms over the past 52 yr. Many of these storms were associated with easterly wind anomalies that departed significantly (2 or more standard deviations) from normal. The examination of climatic anomalies from model forecasts may assist forecasters in identifying significant winter storms in the short range (2–3 days) and potentially out to ranges as long as 7 days when ensemble forecast guidance is utilized.

* Current affiliation: NOAA/National Weather Service, Albany, New York

Corresponding author address: Neil Stuart, NOAA/National Weather Service, 251 Fuller Rd., Albany, NY 12203. Email: neil.stuart@noaa.gov

Abstract

Forecasting major winter storms is a critical function for all weather services. Conventional model-derived fields from numerical weather prediction models most frequently utilized by operational forecasters, such as pressure level geopotential height, temperature fields, quantitative precipitation forecasts, and model output statistics, are often insufficient to determine whether a winter storm represents a large departure from normal, or has the potential to produce significant snowfall. This paper presents a method, using normalized departures from climatology, to assist forecasters in identifying long-duration and potentially significant winter storms. The focus of this paper is on anomalous low- and upper-level wind anomalies associated with winter storms along the U.S. east coast.

Observed and forecast low-level (850 hPa) and upper-level (300 and 250 hPa) easterly wind anomalies are compared with a 30-yr (1961–90) reanalysis climatology. Anomalous easterly low-level winds are correlated with enhanced low-level forcing and frontogenesis. Strong low-level winds can also contribute to enhanced precipitation rates. Upper-level winds that are anomalously below normal, represented as easterly wind anomalies, are also correlated with systems that are cut off from the main belt of westerlies, which may result in slower movement of the system, leading to long-duration events. The proposed method of evaluating easterly wind anomalies is shown to assist in identifying potentially slow-moving storms with extended periods of enhanced precipitation.

To illustrate this method, winter storms on 25–26 December 2002 and 2–4 January 2003 will be compared with past historical winter storms. The results suggest that the low- and upper-level wind anomalies in the two recent snowstorms share common characteristics with several record snowstorms over the past 52 yr. Many of these storms were associated with easterly wind anomalies that departed significantly (2 or more standard deviations) from normal. The examination of climatic anomalies from model forecasts may assist forecasters in identifying significant winter storms in the short range (2–3 days) and potentially out to ranges as long as 7 days when ensemble forecast guidance is utilized.

* Current affiliation: NOAA/National Weather Service, Albany, New York

Corresponding author address: Neil Stuart, NOAA/National Weather Service, 251 Fuller Rd., Albany, NY 12203. Email: neil.stuart@noaa.gov

Save
  • Blaisdell, E. A., 1993: Statistics in Practice. Saunders College Publishing, 653 pp.

  • Bradbury, J. A., Keim B. D. , and Wake C. P. , 2002: United States east coast trough indices at 500 hPa and New England winter climate variability. J. Climate, 15 , 35093517.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Brown, R. F., and Younkin R. J. , 1970: Some relationships between 850 Millibar lows and heavy snow occurrences over the central and eastern United States. Mon. Wea. Rev., 98 , 399401.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Clark, J. H. E., James R. P. , and Grumm R. H. , 2002: A reexamination of the mechanisms responsible for banded precipitation. Mon. Wea. Rev., 130 , 30743086.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Doty, B. E., and Kinter J. L. III, 1995: Geophysical data analysis and visualization using GrADS. Visualization Techniques in Space and Atmospheric Sciences, E. P. Szuszczewicz and J. H. Bredekamp, Eds., NASA, 209–219.

    • Search Google Scholar
    • Export Citation
  • Grumm, R. H., and Nicosia D. J. , 1997: WSR-88D observations of mesoscale precipitation bands over Pennsylvania. Natl. Wea. Dig., 21 , 3. 1023.

    • Search Google Scholar
    • Export Citation
  • Grumm, R. H., and Hart R. , 2001a: Anticipating heavy rainfall: Forecast aspects. Preprints, Symp. on Precipitation Extremes, Albuquerque, NM, Amer. Meteor. Soc., 66–70.

  • Grumm, R. H., and Hart R. , 2001b: Standardized anomalies applied to significant cold season weather events: Preliminary findings. Wea. Forecasting, 16 , 736754.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hart, R. E., and Grumm R. H. , 2001: Using normalized climatological anomalies to rank synoptic-scale events objectively. Mon. Wea. Rev., 129 , 24262442.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hartley, S., and Keables M. J. , 1998: Synoptic associations of winter climate and snowfall variability in New England, USA, 1950–1992. Int. J. Climatol., 18 , 281298.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hirsch, M. E., DeGaetano A. T. , and Colucci S. J. , 2001: An East Coast winter storm climatology. J. Climate, 14 , 882899.

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

  • Kocin, P. J., and Uccellini L. W. , 1990: Snowstorms along the Northeastern Coast of the United States: 1955–1985. Meteor. Monogr., No. 44, Amer. Meteor. Soc., 280 pp.

    • Crossref
    • Export Citation
  • Lamb, P. J., and Peppler R. A. , 1987: North Atlantic Oscillation: Concept and an application. Bull. Amer. Meteor. Soc., 68 , 12181225.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Livezey, R. E., Masutani M. , Leetmaa A. , Rui H. , Ji M. , and Kumar A. , 1997: Teleconnective response of the Pacific–North American region atmosphere to large central equatorial Pacific SST anomalies. J. Climate, 10 , 17871820.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Magsig, M. A., and Page E. M. , 2003: Weather event simulator implementation and future development. Preprints, 19th Conf. on Interactive Information Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology, Long Beach, CA, Amer. Meteor. Soc., CD-ROM, 12.9.

  • Mesinger, F., and Coauthors, 2006: North American Regional Reanalysis. Bull. Amer. Meteor. Soc., 87 , 343360.

  • Michalakes, J., Dudhia J. , Gill D. , Klemp J. , and Skamarock W. , 1998: Design of a next-generation regional weather research and forecast model. Towards Teracomputing, W. Zwieflhofer and N. Kreitz, Eds., World Scientific, 117–124.

    • Search Google Scholar
    • Export Citation
  • Miller, J. E., 1946: Cyclogenesis in the Atlantic coastal region of the United States. J. Meteor., 3 , 3144.

  • Nicosia, D. J., and Grumm R. H. , 1999: Mesoscale band formation in three major northeastern United States snowstorms. Wea. Forecasting, 14 , 346368.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • NOAA, 1959–2003: Storm Data. Vols. 1–45. [Available from the National Climatic Data Center, 151 Patton Avenue, Ashevile, NC 28801-5001.].

  • Stuart, N. A., and Grumm R. , 2004: Evaluating potential impact of significant East Coast winter storms by analysis of upper and low-level wind anomalies. Preprints, 20th Conf. on Weather Analysis and Forecasting, Seattle, WA, Amer. Meteor. Soc., CD-ROM, 9.2.

  • Tracton, M. S., and Kalnay E. , 1993: Operational ensemble prediction at the National Meteorological Center: Practical aspects. Wea. Forecasting, 8 , 379398.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Tracton, M. S., Du J. , Toth Z. , and Juang H. , 1998: Short-Range Ensemble Forecasting (SREF) at NCEP/EMC. Preprints, 12th Conf. on Numerical Weather Prediction, Phoenix, AZ, Amer. Meteor. Soc., 269–272.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 387 111 16
PDF Downloads 283 75 9