Load webfonts asynchronously. A must if you're doing any kind of slabText. See https://github.com/typekit/webfontloader for all supported libraries

webfont.js

jQuery(document).ready(function($) {
  //set up google fonts to load asynchronously with a callback on load
  WebFontConfig = {
    google: {
      families:['Lato:400,700,900,400italic,900italic', 'Oswald'] //the fonts you need
    },
    typekit: {
      id: 'xxxxxx' //supports typekit as well as others
    },
    active: function(familyName, fvd) { //callback when finished
      //resize-justify hero text in header
      $('.header .hero-text').slabText(); //slabtext will now have the right font size
      //hide page initially, then fade in to avoid ugly font-popping
      $('body').addClass('loaded');
      new WOW().init(); //any other visual effects should probably wait until the page shows up, so they go here
    }
  };
  //insert webfont script with above config
  (function() {
    var wf = document.createElement('script');
    wf.src = ('https:' == document.location.protocol ? 'https' : 'http') +
      '://ajax.googleapis.com/ajax/libs/webfont/1/webfont.js';
    wf.type = 'text/javascript';
    wf.async = 'true';
    var s = document.getElementsByTagName('script')[0];
    s.parentNode.insertBefore(wf, s);
  })();
});