how is a low pressure formed in the atmosphere causing cyclones and hurricanes?

Question

how?

Answer 1

Low pressure systems begin as a boundary between two air masses-in the United States, typically cold air to the north and warm air to the south. ( The entire reason a low pressure system forms is to erase this boundary of warm/cold air!) Now, to get this boundary turned into a surface low pressure system, it needs some help from the weather pattern aloft; I'll spare you the details, but there are a few ways to kick start to the formation.

Once this occurs, the low pressure system is born. Warm air will begin to advance northward on the eastern side of the low, and cold air will begin to advance south and eastward to the south and west of the low.( the link at the bottom depicts this better)

For the low to deepen, mass needs to be removed from the column of air above the surface low pressure system ( by the hydrostatic assumption, pressure is simply the mass of all the air above you). This is achieved by another low pressure system at higher levels in the atmosphere, which is behind the original. All the way up the atmosphere at every level, there will be a low, but tilted back. So a surface low in Ohio may have one of it's upper level lows situated above Indiana or Illinois.

Other factors go into how the low deepens, such as whether it has jet stream support . Basically, a lot of physics that isn't necessary here.

The website I've listed below illustrates quite nicely how a surface low pressure forms and matures

Hurricanes are quite different, as their upper level support is not tilted with height-they're mostly vertically stacked, and are referred to as a "warm" core low, whereas the Norwegian cyclone model is a "cold" core low.

Answer 2

This is an excellent question. It is the reason we need Numerical Weather Prediction models comprised of the equations of motion, the thermodynamic equation, the equation of state, and others because it is extremely difficult to project exactly where, when, and even how a cyclone will form without this integrated understanding of the physics. But this is what we do know. The Jet Stream aloft, the location of the troughs of major planetary waves around the globe in the upper atmosphere on constant pressure surfaces, and the formation and advection of vorticity and the rate of change of vorticity all contribute to a circulation or low pressure center developing to the east of a trough and along the polar frontal surface. The NWP models take all these factors into consideration and integrate the differential equations with respect to time such that we obtain a future state of the atmosphere showing where and when the cyclone will develop. I hope this helps a little bit. There is a great deal of physics and mathematics involved in the complete understanding of this very comlicated phenomena in the atmosphere.

Hurricanes although they too are cyclones form under completely different circumstances. They are of tropical origin. They need an ocean surface temperature of around 28C or higher. They require southerly winds to form south of the existing easterly trade winds which produce the vorticity or circulation needed to start up the storm. They require that there be little shear in the vertical so that the heat released from the condensation of water vapor will not be blown away but remain over the storm center and thereby help lower the surface pressure.

Answer 3

The low pressure of the air causes a high pressure volume of air to move towards it.
The Earth rotating underneath the air causes the movement to be in a slight curve relative to an observer on the Earth.
This is known as the Coriolis effect.
The momentum of this curve is amplified by the law of conservation of angular momentum.
It is the same principle that causes water to spiral down a drain.

Answer 4

Simple,pressure.