
In what concerns the weather conditions, the take-off or landing of a flight or an aircraft depends on the following two factors:
Wind speed, wind direction and visibility: When a typhoon is hoisted causing a high speed wind, whether it be a signal number 3, 8, 9 or 10, a flight can still take off or land if the wind direction is suitable for the operation of take-offs and landings. On the contrary, when a typhoon is down, the heavy rain resulting from it might lower the visibility. In such case, a flight cannot take off or land, even though the signal number is removed and the wind.
The aircraft type: Different aircraft types have different capability to withstand wind. When a typhoon is hoisted, if the wind speed can allow a particular aircraft type to take off or land, a flight can therefore perform a take-off or a landing.