MainPage.Xaml.CS

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices.WindowsRuntime;
using Windows.ApplicationModel.Background;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Media.Imaging;
using Windows.UI.Xaml.Navigation;
using static isItFreezing.OpenWeatherProxy;

// The Blank Page item template is documented at https://go.microsoft.com/fwlink/?LinkId=402352&clcid=0x409

namespace isItFreezing
{
    /// <summary>
    /// An empty page that can be used on its own or navigated to within a Frame.
    /// </summary>
    public sealed partial class MainPage : Page
    {
        public MainPage()
        {
            this.InitializeComponent();
        }

        private async void Florida_Loaded(object sender, RoutedEventArgs e)
        {
            int zipcode = 33709;
            RootObject myWeather = await OpenWeatherMapProxy.GetWeatherAsync(zipcode);

            //make the background
            string flWeatherIcon = String.Format("ms-appx:///Assets/Florida/{0}.png", myWeather.weather[0].icon);
            ImageBrush ib = new ImageBrush();
            ib.ImageSource = new BitmapImage(new Uri(flWeatherIcon, UriKind.Absolute));
            ib.Stretch = Stretch.UniformToFill;
            Florida.Background = ib;

            //weather info
            flName.Text = myWeather.name;
            flTemp.Text = "Temp: " + ((int)myWeather.main.temp).ToString()+ " F";
            flHumidity.Text = "Humidity: " + (myWeather.main.humidity).ToString();
            flCondition.Text = myWeather.weather[0].description;

            //polling
            var builder = new BackgroundTaskBuilder();
            builder.Name = "My background trigger";
            builder.SetTrigger(new TimeTrigger(30, false));



        }

        private async void Colorado_Loaded(object sender, RoutedEventArgs e)
        {
            int zipcode = 80918;
            RootObject coWeather = await OpenWeatherMapProxy.GetWeatherAsync(zipcode);

            //make the background
            string coWeatherIcon = String.Format("ms-appx:///Assets/Colorado/{0}.png", coWeather.weather[0].icon);
            ImageBrush ib = new ImageBrush();
            ib.ImageSource = new BitmapImage(new Uri(coWeatherIcon, UriKind.Absolute));
            ib.Stretch = Stretch.UniformToFill;
            Colorado.Background = ib;

            coName.Text = coWeather.name;
            coTemp.Text = "Temp: " + ((int)coWeather.main.temp).ToString() + " F";
            coHumidity.Text = "Humidity: " + (coWeather.main.humidity).ToString();
            coCondition.Text = coWeather.weather[0].description;

        }
    }
}

openweather.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net.Http;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Json;
using System.Text;
using System.Threading.Tasks;

namespace isItFreezing
{
    class OpenWeatherProxy
    {
        public class OpenWeatherMapProxy
        {
            public static async Task<RootObject> GetWeatherAsync(int zipcode)
            {
                var http = new HttpClient();
                string weatherUrl = String.Format("http://api.openweathermap.org/data/2.5/weather?zip={0},us&appid=nope&units=imperial", zipcode);
                var response = await http.GetAsync(weatherUrl);
                var result = await response.Content.ReadAsStringAsync();
                var seralizer = new DataContractJsonSerializer(typeof(RootObject));
                var ms = new MemoryStream(Encoding.UTF8.GetBytes(result));

                var data = (RootObject)seralizer.ReadObject(ms);
                return data;
            }
        }
        [DataContract]
        public class Coord
        {
            [DataMember]
            public double lon { get; set; }

            [DataMember]
            public double lat { get; set; }
        }

        [DataContract]
        public class Weather
        {
            [DataMember]
            public int id { get; set; }

            [DataMember]
            public string main { get; set; }

            [DataMember]
            public string description { get; set; }

            [DataMember]
            public string icon { get; set; }
        }

        [DataContract]
        public class Main
        {
            [DataMember]
            public double temp { get; set; }

            [DataMember]
            public int pressure { get; set; }

            [DataMember]
            public int humidity { get; set; }

            [DataMember]
            public double temp_min { get; set; }

            [DataMember]
            public double temp_max { get; set; }
        }

        [DataContract]
        public class Wind
        {
            [DataMember]
            public double speed { get; set; }

            [DataMember]
            public double deg { get; set; }
        }

        [DataContract]
        public class Clouds
        {
            [DataMember]
            public int all { get; set; }
        }

        [DataContract]
        public class Sys
        {
            [DataMember]
            public int type { get; set; }

            [DataMember]
            public int id { get; set; }

            [DataMember]
            public double message { get; set; }

            [DataMember]
            public string country { get; set; }

            [DataMember]
            public int sunrise { get; set; }

            [DataMember]
            public int sunset { get; set; }
        }

        [DataContract]
        public class RootObject
        {
            [DataMember]
            public Coord coord { get; set; }

            [DataMember]
            public List<Weather> weather { get; set; }

            [DataMember]
            public string @base { get; set; }

            [DataMember]
            public Main main { get; set; }

            [DataMember]
            public int visibility { get; set; }

            [DataMember]
            public Wind wind { get; set; }

            [DataMember]
            public Clouds clouds { get; set; }

            [DataMember]
            public int dt { get; set; }

            [DataMember]
            public Sys sys { get; set; }

            [DataMember]
            public int id { get; set; }

            [DataMember]
            public string name { get; set; }

            [DataMember]
            public int cod { get; set; }
        }
    }
}