During the today (24/08/16) launch of Ariane 5, Stéphane Israël (chairman & CEO) tells that all conditions are good, including a green green weather.
Is it a shortcut for no wind, no rain, or something like that ?
Yes. During Arianespace launch broadcasts, they sometimes show a list of launch conditions. This is a list of about 15 items shown in red or green. If all are green, the launch is proceeded with. An item shown in red means a delay or scrub.
This is similar to the voice poll NASA uses (where each department head says 'Go' or 'No go' a few minutes before launch).