Cyclone bulletins for public updated hourly

I refer to the letter by Jon Thompson regarding information available on the Observatory's Web site ('Storm blown out of proportion,' Post, September 13).

The track Mr Thompson looked at was based on tropical cyclone warnings for international shipping. It is updated at three-hour intervals and is issued two hours after the reference hour because of the time required to collect the synoptic data. Thus the forecast track based on the data at 8am was available at 10am and remained valid until 1pm when it would be updated based on the data at 11am.

For the local situation, members of the public should refer to the latest hourly tropical cyclone bulletins which contain information on the position and strength of the tropical cyclone as well as its effect on Hong Kong. Such information is also posted in the main content page of the Observatory's Web site.

W. M. MA

for Director of the Hong Kong Observatory