Keep in mind that signal 8 is for winds >34 knots, so if the airport is being affected by such wind and if it's all crosswind, there won't be anyone landing or taking off.

Current forecasted tracks look like it's going straight for HKG, but the typhoon is about to go through the gap between Taiwan and the Phillipines. This is a critical time as far as storms are concerned, since both direction and strength can be affected by being near or having to go past land. We'll get a much better idea of the track and how much it will weaken in the next 24 hours.