With the introduction of "prevailing visibility" I think the report on the ATIS or from the ground should reflect the fact that most ot the airfield was clear, (although the METAR will not as far as I know).
I can't remember what the law says here, I think it is "the visbility must be..." rather than "the reported visibility must be...".
I have a feeling that in France it is the reported visibility. In the UK it is the actual visibility. In other words if it came to defending yourself you could be in trouble in France, but off the hook here.