Why is it always sultry before the typhoon comes?

A typhoon is essentially a low-pressure center. Before the arrival of the typhoon, the local air pressure will be affected by the typhoon in advance, and the external air pressure will drop, so the air pressure in the human body will be high, so people will feel "stuffy". Because the typhoon storm has not yet arrived and the temperature is still at a high level, the overall feeling is "sultry".

Related instructions

The formation of typhoon requires the following conditions: the sea surface water temperature is above 26.5℃; Initial disturbance of a positive vorticity; The shear of ambient wind in the vertical direction is very small; Low pressure or cloud disturbance is at least several latitudes from the equator. Because people don't fully understand the formation of typhoons now, the above list is only a necessary condition for the formation of typhoons.

The initial stage of typhoon is tropical depression, and it usually takes about 2 days from the initial low-pressure circulation to the maximum average wind force near the center, only three or four days for the slow one and only a few hours for the fast one. In the development stage, the typhoon continuously absorbs energy until the central air pressure reaches the lowest value and the wind speed reaches the maximum value. After the typhoon landed, under the joint influence of ground friction and insufficient energy supply, it will quickly weaken the death.