An Algorithm for the Detection of Fronts in Wind Profiler Data

Abstract

Abstract An algorithm to detect frontal zones in time–height cross sections of horizontal wind from wind profiler measurements is described. The algorithm works by identifying regions with 1) a strong horizontal temperature gradient, estimated by using a quasigeostrophic thermal wind retrieval, 2) a strong temporal increase in the signal-to-noise ratio at a given range gate, and/or 3) a strong temporal shift in the horizontal winds at a given range gate. The type (e.g., cold or warm) of front is determined by examining the advection field and the characteristics of the boundary. Most weight is given to the horizontal temperature gradient component of the algorithm. A springtime frontal system and an associated baroclinic wave over South Australia are examined using both routine synoptic observations and analyses as well as data from the profiler. Synoptic observations depict a prefrontal trough and two cold fronts at the surface and a deep trough in upper levels. The tropopause is identified at ∼6 km in o...