JSFiddle - React, Tailwind, and code Playground
HTML
<p>Enjoy the rest of your <span data-day="wday"></span>!</p>
JavaScript
function dayOfWeekAsString(idx) {
return ["Sunday", "Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"][idx];
}
var d=new Date();
var day_idx = d.getDay();
var week_day = dayOfWeekAsString(day_idx);
$("p").find("[data-day='wday']").html(week_day);