Chart Calibration Differences

[Verglas]

Can anyone tell me why the METO synoptic charts have isobars at 4mB intervals, and the GFS have them at 5mB ?

Is this just a 'local' thing and not an international standard ?

[johnholmes]

my understanding is that 4mb is the International standard, why 1005 etc with GFS I have no idea.

John

[MAF]

Can anyone tell me why the METO synoptic charts have isobars at 4mB intervals, and the GFS have them at 5mB ?

Is this just a 'local' thing and not an international standard ?

Also can someone explain why the interpretation of the charts can be so varied. i would have thought that after many many years of analysis the reading of the charts wuld be pretty much "in line"

[johnholmes]

aside from GFS and 5 not 4mb I do not know of differences in interepretation of a weather chart

warm front

cold front

occluded front

low

high

again some charts show a high in blue and a low in red

hope that helps

John

[Evo]

I've often wondered about the magnitude of work that goes into producing a fax chart from the raw model output.

One day it would be really nice if I had sufficient understanding, software and time to be able to do that from the GFS output