why pressure drops when bad weather

[arkestra]

Hi,
I wonder why the pressure drops when there's bad weather. And is it because of bad weather that the pressure drops, or is bad weather the consequence of pressure drop?

[wxmann_91]

Areas of low atmospheric pressure usually are associated with enhanced convergence and lift. Areas of high atmospheric pressure usually are associated with subsidence (air sinking). "Bad weather", thus, usually occurs when one goes from an area of high to low atmospheric pressure. Synoptic lift generally will increase and thus rain/thunderstorms, etc.

I hope this answers your question.

[Ptarmigan]

Low pressure allows convection to go up, while high pressure causes air to sink and put a lid on convection.

[arkestra]

Thank you for answers, I know understand a bit. Anyway, I'd like to understand why there's high pressures and low pressures areas... I tried to find info on Wikipedia but still don't have any clue...

[wjs3]

Arkestra:

Take a look at the thread a few below this one called "reading maps" and reiew some of the material coered in the links in there. There are also, I think, some other links in a thread called "mesocyclones questions"

That should help more than wikipedia!

WJS3