Some Characteristic Features of the Jet Stream Complex during Selected Synoptic Conditions

Abstract

This article restates some of the important features in an idealized jet stream complex and presents cross sections showing the structure of jet streams during selected synoptic situations. The jet stream complex consists of the Arctic Front jet stream, two mid-latitude jet streams, and the Subtropical jet stream. The two mid-latitude jet streams, when existing individually, may be identified as the Interpolar Front and Polar Front jet streams, respectively, but when combined are simply termed the Polar Front jet stream. In various synoptic situations this complex is expanded to a state in which each jet stream is a completely distinct entity, or it may be telescoped to such a degree that all jet streams are merged in one broad belt of high speed winds. Synoptic examples are given for four well-defined types of jet stream complex: (1) Arctic, Polar and Subtropical jet streams distinctly separated; (2) separate mid-latitude jet streams (Interpolar and Polar jet streams) and the Subtropical jet stream; (3) mid-latitude westerly jet stream field over a well-developed ridge; (4) combining of the mid-latitude westerly jet stream and the Subtropical jet stream. Descriptions of the air masses, lapse rates, tropopauses and wind profiles in the jet stream complex are given.