Abstract: Observationally motivated idealized initial-value problems of cyclogenesis are studied for quasigeostrophic dynamics. The goals of this investigation are to assess the contributions of normal-mode and nonmodal growth ...

Abstract: umerical experiments are performed to determine the mean state of an axisymmetric hurricane in statistical equilibrium. Most earlier studies used a damping scheme on the temperature field as a parameterization of radiative ...

Abstract: he variability and predictability of axisymmetric hurricanes are determined from a 500-day numerical simulation of a tropical cyclone in statistical equilibrium. By design, the solution is independent of the initial ...

Abstract: A case study is presented of an unusual cold front that affected the east coast of the United States on 22 April 1987. Noteworthy aspects of this front are its genesis behind a preexisting back-door cold front its propagation ...

Abstract: Developing wave packets in the western North Pacific storm track are diagnosed observationally. An abrupt upstream edge to baroclinic wave activity over the western North Pacific facilitates comparisons between the ...

Abstract: The dominant vertical structures for analysis and forecast errors are estimated in midlatitudes using a small ensemble of operational analyses. Errors for fixed locations in the central North Pacific and eastern North ...

Abstract: This paper poses and tests the hypothesis that some of the synoptic-scale and mesoscale tropopause-based disturbances that produce organized vertical motion and induce surface cyclones in the extratropical troposphere are ...

Abstract: Balance dynamics are proposed in a probabilistic framework, assuming that the state variables and the master, or control, variables are random variables described by continuous probability density functions. Balance ...

Abstract: The sensitivity of numerical weather forecasts to small changes in initial conditions is estimated using ensemble samples of analysis and forecast errors. Ensemble sensitivity is defined here by linear regression of analysis ...

Abstract: Singular vectors (SVs) have been applied to cyclogenesis, to initializing ensemble forecasts, and in predictability studies. Ideally, the calculation of the SVs would employ the analysis error covariance norm at the initial ...