Commentary on the First Article in Volume 1 of the National Weather Digest (1976): Operational Diagnostic Applications of Isentropic Analysis

In early 1976, I was a graduate student at the University of Wisconsin-Madison and just had a paper published in Monthly Weather Review (Uccellini, 1975) that was derived from my master’s thesis (under Professor Charles E. Anderson) on large-scale gravity waves capable of initiating convective storms. I was working toward my PhD degree under Professor Donald R. Johnson on the “vertical coupling” of upper and lower-level jet streaks within the indirect transverse circulation found in the exit region of the upper-level jet streak. The coupling process between upper- and low-level jets is related to a mutual mass-momentum adjustment process throughout the troposphere within the jet-streak exit region that could then be applied to describe the vertical shear and differential moisture transports from the lower to middle troposphere that work to destabilize the well-known pre-convective environment prior to the development of severe local storm systems (Uccellini and Johnson 1979). Much of this work on the vertical coupling of upper- and lower level jets was built off the dynamic equations applied in both isobaric (P) and isentropic (θ) vertical coordinates, which necessitated the ability to map the atmospheric circulation patterns in both coordinate systems.