Potential Vorticity Diagnosis of the Severe Convective Regime. Part IV: Comparison with Modeling Simulations of the Moore Tornado Outbreak

Gold, David A.; Nielsen-Gammon, John W.
May 2008
Monthly Weather Review;May2008, Vol. 136 Issue 5, p1612
Academic Journal
A potential vorticity (PV) diagnostic framework is used to explore the sensitivity of the 3 May 1999 Oklahoma City tornado outbreak to the strength of a particular PV anomaly proximate to the geographical region experiencing the tornado outbreak. The results derived from the balanced PV diagnosis agree broadly with those obtained previously in a numerical simulation of the same event, while offering additional insight into the nature of the sensitivity. Similar to the findings of other cases, the balanced diagnosis demonstrates that intensifying (removing) the PV anomaly of interest increases (decreases) the balanced CAPE over the southwestern portion of the outbreak region, reduces (increases) the storm-relative helicity, and increases (reduces) ascent. The latter finding, coupled with the results of the modeling study, demonstrates that intensifying a PV anomaly proximate to an outbreak environment can increase the likelihood that more widespread and possibly less tornadic convection will ensue. The overall results of the balanced diagnosis complement those of other case studies, leading to the formulation of a conceptual model that broadly anticipates how the convective regime will respond to changes in intensity of upper-tropospheric weather features.


Related Articles

  • Potential Vorticity Diagnosis of the Severe Convective Regime. Part III: The Hesston Tornado Outbreak. Gold, David A.; Nielsen-Gammon, John W. // Monthly Weather Review;May2008, Vol. 136 Issue 5, p1593 

    Nonlinear balance potential vorticity (PV) inversion is used to diagnose the sensitivity of the severe convective parameter space to the amplitude of a subsynoptic-scale PV anomaly on 13 March 1990, a day on which a significant tornado outbreak impacted the Great Plains. PV surgery is used to...

  • Jetlet Formation from Diabatic Forcing with Applications to the 1994 Palm Sunday Tornado Outbreak. Hamilton, David W.; Yuh-Lang Lin; Weglarz, Ronald P.; Kaplan, Michael L. // Monthly Weather Review;Aug98, Vol. 126 Issue 8, p2061 

    The three-dimensional responses of simple stably stratified barotropic and baroclinic flows to prescribed diabatic forcing are investigated using a dry, hydrostatic, primitive equation numerical model (the North Carolina State University Geophysical Fluid Dynamics Model). A time-dependent...

  • Potential Vorticity Diagnosis of the Severe Convective Regime. Part II: The Impact of Idealized PV Anomalies. Nielsen-Gammon, John W.; Gold, David A. // Monthly Weather Review;May2008, Vol. 136 Issue 5, p1582 

    Idealized numerical experiments are conducted to understand the effect of upper-tropospheric potential vorticity (PV) anomalies on an environment conducive to severe weather. Anomalies are specified as a single isolated vortex, a string of vortices analogous to a negatively tilted trough, and a...

  • Sensitivities of Simulated Convective Storms to Environmental CAPE. Kirkpatrick, Cody; McCaul, Eugene W.; Cohen, Charles // Monthly Weather Review;Nov2011, Vol. 139 Issue 11, p3514 

    A set of 225 idealized three-dimensional cloud-resolving simulations is used to explore convective storm behavior in environments with various values of CAPE (450, 800, 2000, and 3200 J kg−1). The simulations show that when CAPE == 2000 J kg−1 or greater, numerous combinations of...

  • A Mesovortex within a Near-Equatorial Mesoscale Convective System during TOGA COARE. Chong, Michael; Bousquet, Olivier // Monthly Weather Review;Jun99, Vol. 127 Issue 6, p1 

    Airborne Doppler radar observations are used to investigate the internal structure of a midlevel mesovortex that developed within the rear part of the stratiform precipitation region of a mature-to-decaying mesoscale convective system. This system, composed of several convective elements,...

  • Multiscale Convective Overturning in Mesoscale Convective Systems: Reconciling Observations, Simulations, and Theory. Kain, John S.; Fritsch, J. Michael // Monthly Weather Review;Aug98, Vol. 126 Issue 8, p2254 

    An analysis of how parameterized convection interacts with hydrostatic, explicitly resolved precipitation processes to represent multiscale convective overturning in a mesoscale-resolution numerical simulation is presented. Critically important ingredients of the successful simulation are...

  • A Numerical Study of a Mesoscale Convective System during TOGA COARE. Part II: Organization. Nagarajan, Badrinath; Yau, M.K.; Da-Lin Zhang // Monthly Weather Review;Apr2004, Vol. 132 Issue 4, p1000 

    In Part I, the authors presented a successful numerical simulation of the life cycle of a warm-pool mesoscale convective system (MCS) that occurred on 15 December 1992 during the Tropical Ocean Global Atmosphere Coupled Ocean–Atmosphere Response Experiment. In this study, the simulation...

  • The Numerical Simulation of an Unbalanced Jetlet and Its Role in the Palm Sunday 1994 Tornado Outbreak in Alabama and Georgia. Kaplan, Michael L.; Yuh-Lang Lin; Hamilton, David W.; Rozumalski, Robert A. // Monthly Weather Review;Aug98, Vol. 126 Issue 8, p2133 

    Meso-beta-scale numerical model simulations and observational data are synthesized in an effort to develop a multistage paradigm for use in forecasting tornadic convection in the southeastern United States. The case study to be utilized as an example of the multistage sequence of events is the...

  • Effects of Vertical Shears and Midlevel Dry Air on Tropical Cyclone Developments*. Ge, Xuyang; Li, Tim; Peng, Melinda // Journal of the Atmospheric Sciences;Dec2013, Vol. 70 Issue 12, p3859 

    A set of idealized experiments using the Weather Research and Forecasting model (WRF) were designed to investigate the impacts of a midlevel dry air layer, vertical shear, and their combined effects on tropical cyclone (TC) development. Compared with previous studies that focused on the relative...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics