Passing a variable from script in Jade to express routes or app.js

I'm using the Google GeoLocation API and here is my Jade code:

extends layout

block content
  p Hi
  script(type='text/javascript').
   $(document).ready(function() {

   //I'm not doing anything else, so just leave
   if(!navigator.geolocation) return;

   navigator.geolocation.getCurrentPosition(function(pos) {
   geocoder = new google.maps.Geocoder();
   var latlng = new google.maps.LatLng(pos.coords.latitude,pos.coords.longitude);
   geocoder.geocode({'latLng': latlng}, function(results, status) {
   if (status == google.maps.GeocoderStatus.OK) {
   //Check result 0
   var result = results[0];
   //look for locality tag and administrative_area_level_1
   var city = "";
   var state = "";
   for(var i=0, len=result.address_components.length; i<len; i++) {
   var ac = result.address_components[i];
   if(ac.types.indexOf("locality") >= 0) city = ac.long_name;
   if(ac.types.indexOf("administrative_area_level_1") >= 0) state = ac.long_name;
   }
   //only report if we got Good Stuff
   if(city != '' && state != '') {
   console.log(city);
   }
   } 
   });
   });
   })

I want to make the variable city be accessible in my routes folder and app.js and I cannot find any answers to this problem.