How to display a Google Map based on City selected from a Dropdown Menu

I need to display a map based on a place being selected. I need to know how to change the map based on the dropdown menu. Here is what I have so far, but I cannot seem to figure out how to actually change the map using a selection from the dropdown. I am just completely blanking here. Any references or help is greatly appreciated. Here is the code I currently have.

<script>
    function myMap() {
        var mapCanvas = document.getElementById("map");
        var mapOptions = {  
        center: new google.maps.LatLng(40.685646, -76.195499), zoom: 10 
    };
    var map = new google.maps.Map(mapCanvas, mapOptions);
}

</script>

<div>
    <h2>Please Choose a City</h2>
</div>
<form>
    <fieldset>
        <label>
            Cities
        </label>
        <select id="myCity" name="myCity">
            <option value="None">Select a City</option>
            <option value="PHI">Philadelphia, PA</option>
            <option value="NYC">New York, NY</option>
            <option value="HAR">Hartford, CT</option>
        </select>
    </fieldset>
</form>

Just store the coords by the city key. When the select change, take the value, get the coords and call the method setCenter _(docs) with these coords.

Let me know if something is not clear.

var map;
function myMap() {
  var mapCanvas = document.getElementById("map");
  var mapOptions = {  
    center: new google.maps.LatLng(40.685646, -76.195499), 
    zoom: 10 
  };
  map = new google.maps.Map(mapCanvas, mapOptions);
}

myMap();

var coords = {
  'PHI': '39.953050,-75.163961',
  'NYC': '40.875597,-77.776226',
  'HAR': '41.763633,-72.682662'
};

function changeMap(city) {
  var c = coords[city].split(',');
  map.setCenter(new google.maps.LatLng(c[0], c[1]));
}

#map {
  height: 200px;
}

<script src="https://maps.googleapis.com/maps/api/js"></script>

<div>
  <h2>Please Choose a City</h2>
</div>
<form>
  <fieldset>
    <label>
      Cities
    </label>
    <select id="myCity" name="myCity" onchange="changeMap(this.value)">
      <option value="None">Select a City</option>
      <option value="PHI">Philadelphia, PA</option>
      <option value="NYC">New York, PA</option>
      <option value="HAR">Hartford, CT</option>
    </select>
  </fieldset>
</form>
<div id="map"></div>

http://output.jsbin.com/suhiveb