t.js

$(function() {
  var $citySelect = $('#city-select'),
    STORAGE_ITEM_NAME = 'saveCity';
  
  $citySelect.on('change', function () {  
    var url = $citySelect.val(); 
       
    if (url !== '') {
      localStorage.setItem(STORAGE_ITEM_NAME, url);
      window.location = url;
    }
    return false;
  });
   
  if(localStorage.getItem(STORAGE_ITEM_NAME)){
    $citySelect.val(localStorage.getItem(STORAGE_ITEM_NAME));
  }
});