//Here's how we used to do it in 1.3.2 using setTimeout

    setTimeout(function() {
  $('.mydiv').hide('blind', {}, 500)
}, 5000);



//And here's how you can do it with 1.4 using the delay() feature (this is a lot like sleep)

$(".mydiv").delay(5000).hide('blind', {}, 500);

http://codesnippets.info/jquery/automatically-hide-or-close-elements-after-an-amount-of-time/

Automatically hide or close elements after an amount of time (jQuery)

Automatically hide or close elements after an amount of time (jQuery)

jQuery