Citation

Li PW, Chan PW. Disaster Adv. 2013; 6(3): 71-81.

Copyright

(Copyright © 2013, Shankar Gargh)

DOI

unavailable

PMID

unavailable

Abstract

Thunderstorma are a crucial weather phenomenon for reporting at synoptic stations (as SYNOP) and airports (as METAR/SPECI and location routine/special reports). Traditionally, it is reported based on hearing the thunder and/or seeing the lightning in association with the thunderstorm by the human observer. The use of data from weather radar and lightning location information system (LLIS) for the reporting of thunderstorm is considered in this paper. For this purpose, a method is described in determining the thresholds of radar reflectivity and the distance of cloud-to-ground lightning stroke from the prescribed reflectivity for reporting thunderstorm. It aims at achieving a balance between hit rate and false alarm for detecting thunderstorm. A comprehensive study has been conducted to identify the false alarm cases of LLIS by considering all the available meteorological data. The thresholds are determined to be 32 dBZ and 15 km respectively which are consistent with the results obtained by similar studies of another weather service, but the threshold values are not exactly the same. This points to the importance of establishing the local threshold values for the specific climatological condition of a weather station. Based on such threshold values, a set of guideline of reporting thunderstorm based on radar and LLIS data is proposed. Its impact on thunderstorm climatology is discussed using Hong Kong International Airport (HKIA) as an example.