Connecting the UI to our model - Building a Weather App -> source code crashes repeatedly

@IBOutlet weak var iconView: UIImageView!
@IBOutlet weak var currentTimeLabel: UILabel!
@IBOutlet weak var temperatureLabel: UILabel!
@IBOutlet weak var humidityLabel: UILabel!
@IBOutlet weak var precipitationLabel: UILabel!
@IBOutlet weak var summaryLabel: UILabel!


let apiKey = "962207ed0273d1f2d1ad4a06b856c387"

override func viewDidLoad() {
    super.viewDidLoad()

    let baseURL = NSURL(string: "https://api.forecast.io/forecast/\(apiKey)/")
    let forcastURL = NSURL(string: "39.920032,-86.073166", relativeToURL: baseURL)

    let sharedSession = NSURLSession.sharedSession()
    let downloadTask: NSURLSessionDownloadTask = sharedSession.downloadTaskWithURL(forcastURL!, completionHandler: { (location: NSURL!, response: NSURLResponse!, error: NSError!) -> Void in

        if error == nil {
        let dataObject = NSData(contentsOfURL: location)
        let weatherDictionary: NSDictionary = NSJSONSerialization.JSONObjectWithData(dataObject!, options: nil, error: nil) as NSDictionary


        let currentWeather = Current(weatherDictionary: weatherDictionary)

        /*dispatch_async(dispatch_get_main_queue(), { () ->
                void in
                self.temperatureLabel.text = "\(currentWeather.temperature)"

            })*/



        }
    })
    downloadTask.resume()

}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}