@LH2
Thanks for your help. Yes my question was related to the States.
The thing with the whole SVFR is: at an controlled airport (with tower), you have to get a permission (SVFR clearance) to depart at all. But when the controll tower is not in operation, then you probably not get a clearance this easily. And so I was just wondering if the automated weather report is mandatory (if it reports weather below VFR) to comply with.
Is this forum french orientated? Do you now some aviation forums US orientated?