Overcast enhancement

[Guest jrboddie]

I am thinking about buying AS2004.5 or ASV and have been following the discussions about the representations of OVC conditions with interest.AS2004.5 features "overcast enhancement." What is this exactly? What does AS2004.5 do for overcast effects that are better than the native weather generator in FS?Thanks,Jim

[Damian Clark 1,123]

Hi Jim,Overcast enhancement will double up all OVC layers. For example, if a METAR shows OVC020 (overcast at 2000ft AGL) then 2 overcast layers will be presented, one at 2000ft and another one directly above it (i.e. 4000ft, or wherever the computed ceiling of the first layer is). This effectively makes the OVC layer thicker.It does not always present a fully overcast/blocked layer that prevents all ground/sky visibility. This can be apparent in certain areas depending on station geographics and the visibility setting, as mentioned in the thread you are referring to. In addition, due to station-based wx structures of FS9, the OVC may be limited to the airport that is reporting the data. Other nearby stations that aren't OVC can result in meshed/interpolated clouds even directly adjacent to an OVC station.In short, AS2004.5 makes OVC thicker (with overcast enhancement enabled) but is not a "cure all" to preventing possible "holes" in the layer.Hope that helps!

[Guest glenb]

My memory is a little weak here but I seem to remember that the definition of overcast allows for some holes. There are official definitions for scattered, broken and overcast and I think the overcast may not be 100% overcast.

[Guest jrboddie]

For METAR reporting, the sky is divided into 8 segments. The description of cloud coverage is given by how many segments are completely covered:SKy Clear 0/8FEW >0/8-2/8SCaTtered 3/8-4/8BroKeN 5/8-7/8OVerCast 8/8-Jim