JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.7.2/themes/ui-darkness/jquery-ui.css">
<p>Date: 
    <div id="datepicker"></div>
</p>

JavaScript

/*$( "#datepicker" ).datepicker({
        changeMonth: true,
        changeYear: true,
        yearRange:"-90:+0",
        showOn: "both",
     /*   buttonImage: "http://jqueryui.com/demos/datepicker/images/calendar.gif", //my gif is here
        buttonImageOnly: true
});*/

    $("#datepicker").datepicker({
        changeMonth: true,
        changeYear: true,
        calculateWeek: fisc,
/*        maxDate: '08/25/12',
        minDate: '08/28/11',*/
        showWeek: true
    });

    function fisc(date) {
        var checkDate = new Date(date.getTime());
        checkDate.setDate(checkDate.getDate() + 4 - (checkDate.getDay() || 7));
        var time = checkDate.getTime();
        checkDate.setMonth(7); 
        checkDate.setDate(28);
        var week = (Math.floor(Math.round((time - checkDate) / 86400000) / 7) + 2);
        if (week < 1) {
            week = 52 + week;
        }
        return 'FW: '+week;
    }