The authors would like to thank Dr. Daniel Keyser for his extremely valuable suggestions to this work. Discussions with Drs. Melvyn Shapiro, Stephen Bloom, and Hugo Berberys also contributed greatly. Mr. Joseph Ardizzone and Ms. Laura Rumburg helped the authors with the display of graphics. Finally, the authors wish to thank the reviewers for their helpful comments.
Atlas R., J. C. Jusem, and D. Keyser, 1994: Evolution of a low-level jet in relation to an upper-level baroclinic disturbance east of the Rocky Mountains. Life Cycles of Extratropical Cyclones, Vol. II, Bergen, Norway, University of Bergen 379–384.
Barnes S. L., and B. R. Colman, 1993: Quasigeostrophic diagnosis of cyclogenesis associated with a cutoff extratropical cyclone—The Christmas 1987 storm. Mon. Wea. Rev.,121, 1613–1634.
——, and ——, 1994: Diagnosing an operational numerical model using Q-vector and potential vorticity concepts. Wea. Forecasting,9, 85–102.
Bjerknes, J., and J. Holmboe, 1944: On the theory of cyclones. J. Meteor.,1, 1–22.
Blackburn, M., 1985: Interpretation of ageostrophic winds and implications for jet stream maintenance. J. Atmos. Sci.,42, 2604–2620.
Davies-Jones, R., 1991: The frontogenetical forcing of secondary circulations. Part I: The duality and generalization of the Q vector. J. Atmos. Sci.,48, 497–509.
Eliassen, A., 1962: On the vertical circulations in frontal zones. Geophys. Publ.,24, 147–160.
Hakim, G. J., and L. W. Uccellini, 1992: Diagnosing coupled jet-streak circulations for a northern plains snow band from the operational nested-grid model. Wea. Forecasting,7, 26–48.
Hoskins, B. J., and M. Pedder, 1980: The diagnosis of middle latitude synoptic development. Quart. J. Roy. Meteor. Soc.,106, 707–719.
——, I. Draghici, and H. C. Davies, 1978: A new look at the ω-equation. Quart. J. Roy. Meteor. Soc.,104, 31–38.
Keyser, D., and M. J. Pecnick, 1985: A two-dimensional primitive equation model of frontogenesis forced by confluence and horizontal shear. J. Atmos. Sci.,42, 1259–1282.
——, B. D. Schmidt, and D. G. Duffy, 1989: A technique for representing three-dimensional circulations in baroclinic disturbances. Mon. Wea. Rev.,117, 2463–2494.
——, ——, and ——, 1992: Quasigeostrophic vertical motions diagnosed from along- and cross-isentrope components of the Q vector. Mon. Wea. Rev.,120, 731–741.
Kurz, M., 1992: Synoptic diagnosis of frontogenetic and cyclogenetic processes. Meteor. Atmos. Phys.,48, 77–91.
Lim, G. H., J. R. Holton, and J. W. Wallace, 1991: The structure of ageostrophic wind field in baroclinic waves. J. Atmos. Sci.,48, 1733–1745.
Petterssen, S., 1956: Weather Analysis and Forecasting. 2d ed. McGraw-Hill, 428 pp.
Riehl, H., and Coauthors, 1952: Forecasting in Middle Latitudes.Meteor. Monogr., No. 5, Amer. Meteor. Soc., 80 pp.
Sanders, F., and B. J. Hoskins, 1990: An easy method for estimation of Q-vectors from weather maps. Wea. Forecasting,5, 346–353.
Saucier, S., 1955: Principles of Meteorological Analysis. University of Chicago Press, 438 pp.
Schär, C., and H. Wernli, 1993: Structure and evolution of an isolated semi-geostrophic cyclone. Quart. J. Roy. Meteor. Soc.,119, 57–90.
Shapiro, M. A., 1981: Frontogenesis and geostrophically forced secondary circulations in the vicinity of jet-stream frontal zone systems. J. Atmos. Sci.,38, 954–973.
Uccellini, L. W., and P. J. Kocin, 1987: The interaction of jet streak circulations during heavy snow events along the east coast of the United States. Wea. Forecasting,2, 289–308.