Hong Kong has a sub-tropical climate with distinct seasons. Typhoon season begins in May and ends in November. When a typhoon is approaching, warnings are broadcast on television and radio. There are various degrees of warning signals issued by the Hong Kong Observatory, but when the number 8 signal is in place, most of the city closes down, all schools close. There is a separate warning system for heavy rain.
You can find detailed and up to date weather information on the Hong Kong Observatory Website.
The information below outlines inclement weather procedures.