Seams like your worryig about your childs comfort and I don,t blame you.I would wait till the air Temp warmed up to at least 60 degrees for the childs sake. a cold breeze and water don' t mix well when your that young. AND PLEASE MAKE SURE YOU HAVE A PROPPER FITTING LIFE VEST ON ALL THE YOUNG ONES. Remember in that water temp. it doesn' t take long for hypothermia to set in and if it does you' ll be of no help no matter how tuff people think they are.Be safe and have fun.