• Betts, A. K., 1986: A new convective adjustment scheme. Part I: Observational and theoretical basis. Quart. J. Roy. Meteor. Soc.,112, 677–692.

    • Crossref
    • Export Citation
  • ——, and M. J. Miller, 1986: A new convective adjustment scheme. Part II: Single column tests using GATE wave, BOMEX, and arctic air-mass data sets. Quart. J. Roy. Meteor. Soc.,112, 693–709.

    • Crossref
    • Export Citation
  • Black, T. M., 1994: The new NMC mesoscale Eta model: Description and forecast examples. Wea. Forecasting,9, 265–278.

    • Crossref
    • Export Citation
  • Chen, F., K. Mitchell, J. Schaake, Y. Xue, H.-L. Pan, V. Koren, Q. Y. Duan, M. Ek, and A. Betts, 1996: Modeling of land surface evaporation by four schemes and comparison with FIFE observations. J. Geophys. Res.,101, 7251–7277.

    • Crossref
    • Export Citation
  • Corfidi, S. F., 1998: Some thoughts on the role of mesoscale features played in the 27 May 1997 central Texas tornado outbreak. Preprints, 19th Conf. on Severe Local Storms, Minneapolis, MN, Amer. Meteor. Soc., 177–180.

  • ——, J. H. Merritt, and J. M. Fritsch, 1996: Predicting the movement of mesoscale convective complexes. Wea. Forecasting,11, 41–46.

    • Crossref
    • Export Citation
  • Doswell, C. A., III, H. E. Brooks, and R. A. Maddox, 1996: Flash flood forecasting: An ingredients-based methodology. Wea. Forecasting,11, 560–581.

    • Crossref
    • Export Citation
  • Du, J., S. L. Mullen, and F. Sanders, 1997: Short-range ensemble forecasting of quantitative precipitation. Mon. Wea. Rev.,125, 2427–2459.

    • Crossref
    • Export Citation
  • Gallus, W. A., Jr., and J. F. Bresch, 1997: An intense small-scale wintertime vortex in the midwest United States. Mon. Wea. Rev.,125, 2787–2807.

    • Crossref
    • Export Citation
  • Grell, G. A., 1993: Prognostic evaluation of assumptions used by cumulus parameterizations. Mon. Wea. Rev.,121, 764–787.

    • Crossref
    • Export Citation
  • Hamill, T. M., and S. J. Colucci, 1998: Evaluation of Eta–RSM ensemble probabilistic precipitation forecasts. Mon. Wea. Rev.,126, 711–724.

    • Crossref
    • Export Citation
  • Hong, S.-Y., and H.-L. Pan, 1998: Convective trigger function for a mass-flux cumulus parameterization scheme. Mon. Wea. Rev.,126, 2599–2620.

    • Crossref
    • Export Citation
  • Hoxit, L. R., and Coauthors, 1978: Meteorological analysis of the Johnstown, Pennsylvania flash flood, 19–20 July 1977. NOAA Tech. Rep. ERL 401-APCL 43, 71 pp. [NTIS PB-297412.].

  • Janjic, Z. I., 1994: The step-mountain eta coordinate model: Further developments of the convection, viscous sublayer, and turbulence closure schemes. Mon. Wea. Rev.,122, 928–945.

    • Crossref
    • Export Citation
  • Junker, N. W., and J. E. Hoke, 1990: An examination of Nested Grid Model precipitation forecasts in the presence of moderate-to-strong low-level southerly inflow. Wea. Forecasting,5, 333–344.

    • Crossref
    • Export Citation
  • Kain, J. S., and J. M. Fritsch, 1992: The role of the convective “trigger function” in numerical forecasts of mesoscale convective systems. Meteor. Atmos. Phys.,49, 93–106.

    • Crossref
    • Export Citation
  • ——, and ——, 1993: Convective parameterization for mesoscale models: The Kain–Fritsch scheme. The Representation of Cumulus Convection in Numerical Models, Meteor. Monogr., No. 46, Amer. Meteor. Soc., 165–170.

    • Crossref
    • Export Citation
  • Maddox, R. A., L. R. Hoxit, C. F. Chappell, and F. Caracena, 1978:Comparison of meteorological aspects of the Big Thompson and Rapid City flash floods. Mon. Wea. Rev.,106, 375–389.

    • Crossref
    • Export Citation
  • ——, C. F. Chappell, and L. R. Hoxit, 1979: Synoptic and meso-α aspects of flash flood events. Bull. Amer. Meteor. Soc.,60, 115–123.

    • Crossref
    • Export Citation
  • Markowski, P. M., E. N. Rasmussen, J. M. Straka, and D. C. Dowell, 1998a: Observations of low-level baroclinicity generated by anvil shadows. Mon. Wea. Rev.,126, 2959–2971.

    • Crossref
    • Export Citation
  • ——, J. M. Straka, E. N. Rasmussen, and D. O. Blanchard, 1998b: Variability of helicity during VORTEX. Mon. Wea. Rev.,126, 2942–2958.

    • Crossref
    • Export Citation
  • Mesinger, F., 1998: Comparison of quantitative precipitation forecasts by the 48- and by the 29-km Eta model: An update and possible implications. Preprints, 12th Conf. on Numerical Weather Prediction, Phoenix, AZ, Amer. Meteor. Soc., J22–J23.

  • ——, Z. I. Janjic, S. Nickovic, D. Gavrilov, and D. G. Deaven, 1988:The step mountain coordinate: Model description and performance for cases of alpine cyclogenesis and for a case of an Appalachian redevelopment. Mon. Wea. Rev.,116, 1493–1518.

    • Crossref
    • Export Citation
  • Miller, R. C., 1972: Note on Analysis and Severe Storm Forecasting Procedures of the Air Force Global Weather Central. Tech. Rep. 200 (Rev. 1975), Air Weather Service, U.S. Air Force, 190 pp. [Available from Air Weather Service, Scott Air Force Base, IL 62225.].

  • Molinari, J., and M. Dudek, 1986: Implicit versus explicit convective heating in numerical weather prediction models. Mon. Wea. Rev.,114, 1822–1831.

    • Crossref
    • Export Citation
  • ——, and ——, 1992: Parameterization of convective precipitation in mesoscale numerical models: A critical review. Mon. Wea. Rev.,120, 326–344.

    • Crossref
    • Export Citation
  • Murphy, J. M., 1988: The impact of ensemble forecasts on predictability. Quart. J. Roy. Meteor. Soc.,114, 463–494.

    • Crossref
    • Export Citation
  • Nicolini, M., K. M. Waldron, and J. Paegle, 1993: Diurnal oscillations of low-level jets, vertical motion and precipitation: A model case study. Mon. Wea. Rev.,121, 2588–2610.

    • Crossref
    • Export Citation
  • Rogers, E., and Coauthors, 1998: Changes to the NCEP Operational“Early” Eta Analysis/Forecast System. NWS Tech. Procedures Bull. 447, National Oceanic and Atmospheric Administration/National Weather Service, 14 pp. [Available from National Weather Service, Office of Meteorology, 1325 East–West Highway, Silver Spring, MD 20910.].

  • Rogers, R. F., and J. M. Fritsch, 1996: A general framework for convective trigger functions. Mon. Wea. Rev.,124, 2438–2452.

    • Crossref
    • Export Citation
  • Romero, R., C. Ramis, S. Alonso, C. A. Doswell III, and D. Stensrud, 1998: Mesoscale model simulations of three heavy precipitation events in the western Mediterranean region. Mon. Wea. Rev.,126, 1859–1881.

    • Crossref
    • Export Citation
  • Schneider, R. S., N. W. Junker, M. T. Eckert, and T. M. Considine, 1996: The performance of the 29 km Meso Eta model in support of forecasting at the Hydrometeorological Prediction Center. Preprints, 11th Conf. on Numerical Weather Prediction, Norfolk, VA, Amer. Meteor. Soc., J111–J114.

  • Senesi, S., P. Bougeault, J.-L. Cheze, P. Cosentino, and R.-M. Thepenier, 1996: The Vaison-la-Romaine flash flood: Mesoscale analysis and predictability issues. Wea. Forecasting,11, 417–442.

    • Crossref
    • Export Citation
  • Stensrud, D. J., and J. M. Fritsch, 1994a: Mesoscale convective systems in weakly forced large-scale environments. Part II: Generation of a mesoscale initial condition. Mon. Wea. Rev.,122, 2068–2083.

  • ——, and ——, 1994b: Mesoscale convective systems in weakly forced large-scale environments. Part III: Numerical simulations and implications for operational forecasting. Mon. Wea. Rev.,122, 2084–2104.

    • Crossref
    • Export Citation
  • Vaidya, S. S., and S. S. Singh, 1997: Thermodynamic adjustment parameters in the Betts–Miller scheme of convection. Wea. Forecasting,12, 819–825.

    • Crossref
    • Export Citation
  • Weisman, M. L., W. C. Skamarock, and J. B. Klemp, 1997: The resolution dependence of explicitly modeled convective systems. Mon. Wea. Rev.,125, 527–548.

    • Crossref
    • Export Citation
  • Zhang, D.-L., and J. M. Fritsch, 1988: Numerical sensitivity experiments of varying model physics on the structure, evolution, and dynamics of two mesoscale convective systems. J. Atmos. Sci.,45, 261–293.

    • Crossref
    • Export Citation
  • ——, J. S. Kain, J. M. Fritsch, and K. Gao, 1994: Comments on“Parameterization of convective precipitation in mesoscale numerical models. A critical review.” Mon. Wea. Rev.,122, 2222–2231.

    • Crossref
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 235 77 4
PDF Downloads 63 37 0

Eta Simulations of Three Extreme Precipitation Events: Sensitivity to Resolution and Convective Parameterization

View More View Less
  • 1 Department of Geological and Atmospheric Science, Iowa State University, Ames, Iowa
Restricted access

Abstract

A versatile workstation version of the NCEP Eta Model is used to simulate three excessive precipitation episodes in the central United States. These events all resulted in damaging flash flooding and include 16–17 June 1996 in the upper Midwest, 17 July 1996 in western Iowa, and 27 May 1997 in Texas. The episodes reflect a wide range of meteorological situations: (i) a warm core cyclone in June 1996 generated a meso-β-scale region of excessive rainfall from echo training in its warm sector while producing excessive overrunning rainfall to the north of its warm front, (ii) a mesoscale convective complex in July 1996 produced excessive rainfall, and (iii) tornadic thunderstorms in May 1997 resulted in small-scale excessive rains.

Model sensitivity to horizontal resolution is investigated using a range of horizontal resolutions comparable to those used in operational and quasi-operational forecasting models. Sensitivity tests are also performed using both the Betts–Miller–Janjic convective scheme (operational at NCEP in 1998) and the Kain–Fritsch scheme. Variations in predicted peak precipitation as resolution is refined are found to be highly case dependent, suggesting forecaster interpretation of increasingly higher resolution model quantitative precipitation forecast (QPF) information will not be straightforward. In addition, precipitation forecasts and QPF response to changing resolution are both found to vary significantly with choice of convective parameterization.

Corresponding author address: Dr. William A. Gallus Jr., Department of Geological and Atmospheric Science, Iowa State University, 3025 Agronomy Hall, Ames, IA 50011.

Email: wgallus@iastate.edu

Abstract

A versatile workstation version of the NCEP Eta Model is used to simulate three excessive precipitation episodes in the central United States. These events all resulted in damaging flash flooding and include 16–17 June 1996 in the upper Midwest, 17 July 1996 in western Iowa, and 27 May 1997 in Texas. The episodes reflect a wide range of meteorological situations: (i) a warm core cyclone in June 1996 generated a meso-β-scale region of excessive rainfall from echo training in its warm sector while producing excessive overrunning rainfall to the north of its warm front, (ii) a mesoscale convective complex in July 1996 produced excessive rainfall, and (iii) tornadic thunderstorms in May 1997 resulted in small-scale excessive rains.

Model sensitivity to horizontal resolution is investigated using a range of horizontal resolutions comparable to those used in operational and quasi-operational forecasting models. Sensitivity tests are also performed using both the Betts–Miller–Janjic convective scheme (operational at NCEP in 1998) and the Kain–Fritsch scheme. Variations in predicted peak precipitation as resolution is refined are found to be highly case dependent, suggesting forecaster interpretation of increasingly higher resolution model quantitative precipitation forecast (QPF) information will not be straightforward. In addition, precipitation forecasts and QPF response to changing resolution are both found to vary significantly with choice of convective parameterization.

Corresponding author address: Dr. William A. Gallus Jr., Department of Geological and Atmospheric Science, Iowa State University, 3025 Agronomy Hall, Ames, IA 50011.

Email: wgallus@iastate.edu

Save