CORRELATIONS BETWEEN HAIL EVENTS AND RADAR ECHOES IN TRANSYLVANIA
RECKERTH U. D.
ABSTRACT. - Correlations between hail events and radar echoes in Transylvania. Over 500 hail events reported across Transylvania by meteorological and hydrological stations, with several large hail events (i.e. hail diameter ≥ 2 cm), were studied during 2004-2014. The purpose of this study was to determine the correlations between the hail events, especially the hail size, and different radar echoes, such as reflectivity, vertically integrated liquid, echo tops of the clouds, and instability indices, such as the vertical totals index, in order to provide useful information regarding forecast of hail, especially large hail. The radar data were measured by the WSR-98D Doppler radar from Bobohalma-Tarnaveni, Mures county, placed in central Transylvania. I have also studied the use of vertically integrated liquid density as an indicator for the size of hail in thunderstorms, applied in Transylvania for operational use. The methodology used in deriving this comparison is provided to assist other operational weather forecasters in developing VIL Density vs. hail size correlation.
Keywords: hail, meteorological radar, VIL, weather forecast.