1000MB pressure etc

[Lazz]

Hi all

Not sure if this is the correct place to ask this but what exactly to the different numbers on the pressure readings mean? Cause I've noticed they always seem to be in the late 980's to the early 1000's.

[Gray-Wolf]

Hi all

Not sure if this is the correct place to ask this but what exactly to the different numbers on the pressure readings mean? Cause I've noticed they always seem to be in the late 980's to the early 1000's.

Those numbers are the pressure at sea level in millibars. The average sea level pressure (globally I think) is 1013mb so every number lower than this represents low pressure , the numbers above 1013mb equate to high pressure.

With High pressure numbers you would generaly expect 'fine' weather and with low pressure you would expect worse weather.

I'm sure others can fill in the why's and how's and move this to the learners area

Edited October 5, 2006 by Gray-Wolf

[Paul]

The figures correspond to the air pressure at sea level in that location. As a general rule - low pressure = unsettled weather and high pressure = settled weather. Wind circulates around low pressure areas anti clockwise and around high pressure areas clockwise.

[johnholmes]

in the northern hemisphere

[johnholmes]

the 'average' pressure for the whole world exactly is 1013.2mb. But it depends on the pressure pattern at any one time what is called High or Low, but that number gives a guide.

John