Jean, We do simulate the same conditions available under the default weather engine anlong with any injectors out there. Overcast condtions are presented as either a flat layer(low setting in the SM UI) or as a heavy Cumulus Congestus layer (Medium/High setting in the SM UI) You can force a cirrus layer to be present all the time or let it be present if the weather engine says one is there. We also simulate standard cumulus conditions ie few, scattered or broken along with thunderheads and towering cumulus.....