People going outdoors during rainy or stormy weather can use the Hong Kong Observatory's new lightning location information service to locate and track thunderstorms. Lightning strike locations will be displayed in graphical form on the Observatory's website and PDA website.

The webpage will be updated every five minutes enabling the visualisation of storm cell movements through map animations divided into New Territories West, New Territories East, Lantau, and Hong Kong Island and Kowloon.

An alert function will be provided on the lightning webpage which will be displayed when the network has detected lightning in one of the regions selected.

Storm tracer: The Hong Kong Observatory's new lightning location information service locates and tracks thunderstorms.

Dial-a-weather

A condensed version of the lightning location information will be available in the hourly weather bulletin broadcast on radio and television. The information will also be accessible from the Dial-a-Weather system (1878 200), updated every 15 minutes.

When using the lightning information, people should also read the Thunderstorm Warning issued by the Observatory, and check radar images and the rainfall distribution map on its website to gain a comprehensive view of the thunderstorm situation and take necessary precautions. In the past 15 years, 35 people have been struck by lightning in Hong Kong - six fatally.

Special users like construction companies and recreational facility operators will benefit from the new service, which can help them decide whether to suspend outdoor operations.

Personal service

Customised lightning services will be provided on a cost-recovery basis to special clients through a dedicated webpage. Automatic audio and visual alarms will be triggered when lightning strikes occur within an area of interest centred at the client's pre-defined location. Those interested in the service can call 2926 8376.

The Observatory recently set up the lightning location network with Guangdong and Macau meteorological authorities. It consists of five sensors installed at Chung Hom Kok, Tsim Bei Tsui, Sha Tau Kok, Sanshui in Guangdong and Taipa in Macau, monitoring lightning over the Pearl River Estuary.

Location is calculated using the time of arrival and direction of the electromagnetic waves generated by the lightning discharges as detected by network sensors. For more details, click here.