A three-dimensional numerical sensitivity study of convection over the Florida peninsula

The Florida peninsula has the highest annual number of days with thunderstorms in the United States, partly due to sea breeze convergence. A three-dimensional mesoscale planetary boundary layer (PBL) model with the E-ε turbulence closure is used to investigate the relationship between sea breeze convergence and convection over the peninsula for two ambient wind cases during typical summer days.It is found that the spatial and temporal variation of the sea breeze convergence zones and the associated convective activities depend to a large extent on the direction and magnitude of the ambient wind. For the case of southeasterly ambient winds, a strong convergence zone and hence significant rainfall occur primarily along the west coast of the peninsula. The convergence zone and the associated rainfall shift towards the east coast for the case of southwesterly ambient winds. These are in agreement with the observations. In contrast to the southeasterly and southwesterly ambient winds, an intense convergence zone and rainfall occur near both coastlines of the peninsula under light ambient winds.It is also found that lake Okeechobee has a substantial influence on south Florida's mesoscale weather. A cloudless region is always present over the lake at least until late afternoon due to its own lake breeze circulation. Finally, increased roughness of the land surface appears to influence the temporal and spatial variation of the convection by determining the intensity of the vertical turbulent transport of heat and momentum.

[1]  R. Pielke,et al.  Numerical Experiments on the Influence of the Mesoscale Circulation on the Cumulus Scale. , 1976 .

[2]  S. Raman,et al.  A comparative study of numerical advection schemes featuring a one-step modified WKL algorithm , 1991 .

[3]  E. L. Fisher,et al.  A THEORETICAL STUDY OF THE SEA BREEZE , 1961 .

[4]  G. Mellor,et al.  Development of a turbulence closure model for geophysical fluid problems , 1982 .

[5]  R. A. Pearson.  Properties of the Sea Breeze Front as Shown by a Numerical Model , 1973 .

[6]  Paul Kutler,et al.  Second- and Third-Order Noncentered Difference Schemes for Nonlinear Hyperbolic Equations , 1973 .

[7]  Y. Mahrer,et al.  Verification Analysis of the University of Virginia Three-Dimensional Mesoscale Model Prediction over South Florida for 1 July 1973 , 1978 .

[8]  Horace R. Byers,et al.  CAUSES OF THUNDERSTORMS OF THE FLORIDA PENINSULA , 1948 .

[9]  Sethu Raman,et al.  Numerical simulation of January 28 cold air outbreak during GALE part II: The mesoscale circulation and marine boundary layer , 1991 .

[10]  Alan J. Thorpe,et al.  Radiation conditions for the lateral boundaries of limited‐area numerical models , 1981 .

[11]  S. Raman,et al.  Numerical simulation of January 28 cold air outbreak during GALE Part I: The model and sensitivity tests of turbulence closures , 1991 .

[12]  W. Cotton.  On Parameterization of Turbulent Transport in Cumulus Clouds , 1975 .

[13]  Roger A. Pielke,et al.  The Effects of Topography on Sea and Land Breezes in a Two-Dimensional Numerical Model , 1977 .

[14]  E. F. Bradley,et al.  Flux-Profile Relationships in the Atmospheric Surface Layer , 1971 .

[15]  M. Estoque,et al.  The Sea Breeze as a Function of the Prevailing Synoptic Situation , 1962 .

[16]  N. L. Frank,et al.  Summer Shower Distribution Over the Florida Peninsula as Deduced from Digitized Radar Data , 1967 .

[17]  Roger A. Pielke,et al.  A Three-Dimensional Numerical Model of the Sea Breezes Over South Florida , 1974 .

[18]  R. McPherson,et al.  A Numerical Study of the Effect of a Coastal Irregularity on the Sea Breeze , 1970 .

[19]  D. Durran,et al.  An Upper Boundary Condition Permitting Internal Gravity Wave Radiation in Numerical Mesoscale Models , 1983 .

[20]  I. Orlanski.  A Simple Boundary Condition for Unbounded Hyperbolic Flows , 1976 .

[21]  J. Neumann,et al.  A Theoretical Study of the Land and Sea Breeze Circulation. , 1971 .

[22]  C. J. Neumann.  The Thunderstorm Forecasting System at the Kennedy Space Center , 1971 .