Fine-scale observations of a dryline during the International H2O Project

The dryline has long been associated with the development of severe thunderstorms in the southern Plains during the spring and early summer months. The propagation and structure of the dryline are closely tied to surface processes that are neither well-understood nor well-resolved with current observational capabilities. As a result, large errors in forecasts of dryline position and structure are often seen. Current (and pending/proposed) radar technology will undoubtedly improve our understanding in the years to come.

The presentation will be devoted to very-fine scale radar observations taken with the mobile UMass W-band radar during a double-dryline IHOP event on 22 May 2002 in the Oklahoma panhandle. The observations will be placed in the context of the dryline secondary circulation, which describes flow in a plane normal to the dryline. The narrow half-power beamwidth of the antenna on the W-band (0.18 deg) permitted the measurements of narrow channels of upward and downward vertical velocity greater in absolute magnitude than that previously reported in dryline field studies.