FSMETAR

Hi,
Is there anyone in here using FSMETAR for weather? IN fact I am trying to define a weather situation with low visibility conditions and low temperatres but ny question has to do with the way FS2002 uses the METAR information. For example, when I specify OVC015 which is an overcast coverage in 1500ft, FS2002 applies a bottom and top altitude of the specifed layer. I noticed that with even worse conditions like OVC008 the layer was expanded down the runway in a sea-level airport.
Has anyone gone into more depth on the subject?
Is there anyone in here using FSMETAR for weather? IN fact I am trying to define a weather situation with low visibility conditions and low temperatres but ny question has to do with the way FS2002 uses the METAR information. For example, when I specify OVC015 which is an overcast coverage in 1500ft, FS2002 applies a bottom and top altitude of the specifed layer. I noticed that with even worse conditions like OVC008 the layer was expanded down the runway in a sea-level airport.
Has anyone gone into more depth on the subject?