Q:

Google Maps Circle

I am trying to load data from an API then display it using circles. I am able to create markers with the data points but not circles. I am following this example here from Google's documentation.
What I expect to happen is in the for loop, using center: new google.maps.LatLng(well.location.latitude, well.location.longitude) would suffice to create the center points. However, that doesn't seem to work. Everything else is the same as the example (will modify later).
I expected this to work because earlier in the example, I am able to use $.each to display markers using field.location.latitude, field.location.longitude which is essentially the same thing (or so I think).
Can I not make circles within the $.getJSON function like I can with markers? Is it happening "out of sync"? I'm still trying to learn how to process async events.
Fiddle here.
HTML:
<head>
    <script src="http://maps.googleapis.com/maps/api/js"></script>
    <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script>
</head>
<body>
    <div id="map"></div>
</body>

CSS:
#map {
    border: 1px solid black;
    margin: 0 auto;
    width: 500px;
    height: 300px;
}

JavaScript
var map;
var mapProp;
var url;
var marker;
var markers = [];
var infoWindow;
var wellCircle;

function initMap() {
    mapProp = {
        center: new google.maps.LatLng(39.0, -105.782067),
        zoom: 6,
        mapTypeId: google.maps.MapTypeId.TERRAIN
    };
    map = new google.maps.Map(document.getElementById("map"), mapProp);
    infoWindow = new google.maps.InfoWindow({
        content: "hello world"
    });
};

function addMarker(lat, lng) {
    marker = new google.maps.Marker({
        position: new google.maps.LatLng(lat, lng),
        map: map
    });
    markers.push(marker);
    //console.log(markers);
};
$(document).ready(function() {
    url = 'https://data.colorado.gov/resource/hfwh-wsgi.json?&$limit=500';
    initMap();
    $.getJSON(url, function(data) {
        //console.log(data);
        for (var i = 0; i < data.length; i++) {
            //console.log(data[i].location.latitude + ", " + data[i].location.longitude);
        };
        $.each(data, function(i, field) {
            addMarker(field.location.latitude, field.location.longitude);
        });
        for (var well in data) {
            wellCircle = new google.maps.Circle({
                strokeColor: '#FF0000',
                strokeOpacity: 0.8,
                strokeWeight: 2,
                fillColor: '#FF0000',
                fillOpacity: 0.35,
                map: map,
                center: new google.maps.LatLng(well.location.latitude,
                    well.location.longitude),
                radius: 100000
            });
        };
    });
});

A:

data is an array, either iterate through it, or use $.each (or .forEach).
for (var i=0; i < data.length; i++) {
    var wellCircle = new google.maps.Circle({
        strokeColor: '#FF0000',
        strokeOpacity: 0.8,
        strokeWeight: 2,
        fillColor: '#FF0000',
        fillOpacity: 0.35,
        map: map,
        center: new google.maps.LatLng(data[i].location.latitude, data[i].location.longitude),
        radius: 10000
    });
};

or (like you did with the markers):
$.each(data, function(i, well) {
    var wellCircle = new google.maps.Circle({
        strokeColor: '#FF0000',
        strokeOpacity: 0.8,
        strokeWeight: 2,
        fillColor: '#FF0000',
        fillOpacity: 0.35,
        map: map,
        center: new google.maps.LatLng(well.location.latitude, well.location.longitude),
        radius: 10000
    });
});

code snippet:

var map;
var mapProp;

function initMap() {
  mapProp = {
    center: new google.maps.LatLng(39.0, -105.782067),
    zoom: 6,
    mapTypeId: google.maps.MapTypeId.TERRAIN
  };
  map = new google.maps.Map(document.getElementById("map"), mapProp);
  infoWindow = new google.maps.InfoWindow({
    content: "hello world"
  });
};

$(document).ready(function() {
  url = 'https://data.colorado.gov/resource/hfwh-wsgi.json?&$limit=500';
  initMap();
  $.getJSON(url, function(data) {
    $.each(data, function(i, well) {
      var wellCircle = new google.maps.Circle({
        strokeColor: '#FF0000',
        strokeOpacity: 0.8,
        strokeWeight: 2,
        fillColor: '#FF0000',
        fillOpacity: 0.35,
        map: map,
        center: new google.maps.LatLng(well.location.latitude, well.location.longitude),
        radius: 10000
      });
    });
  });
});
body, html {
  margin: 0px;
  padding: 0px;
  width: 100%;
  height: 100%;
}
#map {
  border: 1px solid black;
  margin: 0 auto;
  width: 99%;
  height: 99%;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://maps.googleapis.com/maps/api/js"></script>
<div id="map"></div>

