A Comparison of the Detectability of Microbursts in Orlando, Florida, by Two C-Band Doppler Radars

Abstract

Microbursts continue to pose a serious problem to the aviation industry. Fortunately, Doppler weather radars are capable of detecting microbursts quite successfully. This study gives the results of a comparison of 84 microbursts detected by a pair of C-band Doppler radars near Orlando during the summer of 1991. The study shows that microbursts were detectable at nearly the same locations (average positional difference of 1 km) and times (average time of detection differed by only 23 s) by both radars. The differential wind velocity detected by each of the radars was also quite similar (average difference of only 0.01 m s?1) as were the radar reflectivity factors (average difference was 1 dB). The conclusion from this is that a C-band radar located anywhere near an airport should be fully capable of detecting hazardous wet-microburst events. Attenuation of the C-band signals was never strong enough to make microbursts undetectable. Bemuse all events were wet microbursts (average reflectivity was 47 dBZ) and the maximum reflectivity difference seen for any microburst was only 10 dB, all events would have been much stronger than the minimum detectable reflectivity at the relatively short ranges used in this study. Attenuation might, however, be a problem for the detection of weak gust fronts.