The location-specific lightning alert is a free online service provided by the Hong Kong Observatory. Users simply select the location of interest in the Location-specific Lightning Alert webpage. An alert will be automatically sent out (with pop-up message and sound) when lightning is detected within the specified ranges over the past 5 minutes.
Up to three alert ranges, with a minimum size of 5 km to a maximum of 50 km from the location of interest can be selected. Alternatively, users can select a region of interest from one of the four system-predefined regions (click here to view the predefined regions).
Your alert setting will automatically be stored in your computer if you have enabled cookies in your browser. When you click the button to open the selection menu next time, your previous alert setting will re-appear in the menu.
If you have a slow Internet connection or if the interactive lightning map cannot be displayed properly in the browser of your mobile device, you may browse the PDA version of the webpage (http://pda.hko.gov.hk/llise.htm), which shows the latest lightning locations in a simpler graphical format.