A CodePen by Darío Javier Cravero.

index.html

<div class=hover-me>HOVER THIS</div>
<div class=helper></div>

script.js

var helpers = ['Hover 1', 'Hover 2', 'Hover 3'],
    index = 0,
    time = 2000,
    start_over = false,
    interval, timeout;

$('.hover-me').on('mouseover', function() {
  $('.helper').addClass('active').text(helpers[index++]);
  interval = setInterval(function() {
    if (index > helpers.length) index = 0;
    $('.helper').addClass('transition');
    timeout = setTimeout(function() {
      $('.helper').text(helpers[index++]).removeClass('transition');
    }, time/4);
  }, time);
}).on('mouseout', function() {
  $('.helper').removeClass('active transition').text('');
  clearInterval(interval);
  clearTimeout(timeout);
  index = start_over ? 0 : index-1;
});

style.css

.helper {
  -webkit-transition: opacity 0.5s ease-in-out;
  opacity: 0;
}
.helper.active {
  opacity: 1;
}
.helper.transition {
  opacity: 0;
}