Some examples of surface wind field analysis based on Jindalee skywave radar data

During February and March 1986, maps of wind direction were obtained at 40 km resolution using the Australian Jindalee skywave radar over large areas surrounding both developing and non-developing tropical cloud clusters. After resolution of the left-right ambiguity in the Jindalee data by means of standard in situ surface observations and satellite data, substantial differences were evident between the two systems. The developing system showed a persistent surface vortex even though the associated cloud pattern configuration changed with time during the developmental phase of the vortex. The non-developer showed no evidence of an associated vortex. Jindalee data therefore indicated the potential to discriminate differences between such systems. The Jindalee wind direction data also enabled excellent locations of the centre of the developing vortex before and after it was classified as a tropical cyclone. The average difference from the Australian Bureau of Meteorology operational track was only 30 km.