What you are seeing is not CFD related (so no matter it is OFF or ON) but the thermals (related to the “Show 3D thermal” option in the weather window at the bottom"). They should not appear since you have it turned off. Could you activate and deactivate it to check if the visualization stays on or goes away ?
FYI, CFD are those visualization lines around the aircraft:
Could you indicate the exact location where you took your screenshots and 1st layer cloud settings to try to reproduce ?