When initially learning to fly (before your first solo) you should stick to a 10kt limit. Anything over that, due to the turbulence associated with the higher winds, It becomes counter productive. You are still learning what each control input does and how the A/C reacts to these inputs. When the A/C is getting thrown around by turbulence it's hard for the newbie to tell if it's them or the turbulence. Also the down winds can get too quick for your newly aquiring skills. After you have learned enough to fly solo on the lighter days try it with more wind and turbulence.