Abstract: A 17-day period during November 1980 is investigated to obtain insight into differing large-scale 500 mb circulation changes during three consecutive synoptic-scale cyclone ?events? Each event is defined by at least one ...

Abstract: Analyses of winter cyclone frequency and deepening rates are presented for a 10-year period over the eastern United States and western Atlantic Ocean. Results are presented for 1° latitude-longitude quadrangles. The data ...

Abstract: Four cases of tropospheric weather systems (two sea level cyclones, one sea level anticyclone, and one blocking midtropospheric anticyclone) are investigated with the goal of understanding the role of stratospheric versus ...

Abstract: The local preconditioning of the midtropospheric planetary-scale flow prior to the onset of a blocking episode during January 1985 is investigated. The preconditioned flow is anomalously diffluent, or characterized by ...

Abstract: Large-scale circulation changes attending explosive surface cyclogenesis are quantitatively examined in two cases selected from recent winter seasons. Both cases feature a rapidly deepening surface cyclone over the western ...

Abstract: The opposition between two block-onset forcing mechanisms, previously identified in midtropospheric analyses over the Southern Hemisphere midlatitudes, is analytically interpreted with an idealized model. These mechanisms ...

Abstract: generalized frictionless, adiabatic geostrophic zonal wind tendency equation is derived to diagnose the nonquasigeostrophic forcings to blocking onset in the Southern Hemisphere through case study and composite analysis. ...

Abstract: The relative importance of interactions between deformation and potential vorticity (PV) as a block-onset mechanism is examined in 30 cases of atmospheric blocking over the Southern Hemisphere (SH). The blocking cases are ...

Abstract: A set of thirty 30-day mean 500-mb height anomaly forecasts run from National Meteorological Center initial analyses by the NCAR Community Climate Model is examined in order to learn if the forecast accuracy can be estimated ...

Abstract: The study investigates the local climatological minimum of tropical cyclogenesis over the eastern Caribbean Sea. This area, colloquially known by forecasters as the ?hurricane graveyard,? is located within the deep tropical ...