Error : cannot find an initialiser for type 'NSData' that accepts an argument list

 //
//  ViewController.swift
//  Stormy
//
//  Created by Kh. Deepalaxmi on 29/07/15.
//  Copyright (c) 2015 Kh. Deepalaxmi. All rights reserved.
//

import UIKit

class ViewController: UIViewController {

    private let forecastAPIKey = "d65a97d1550c7a4f2748e50a117ef32c"

    @IBOutlet weak var currentTemperatureLabel: UILabel?
    @IBOutlet weak var currentHumidityLabel: UILabel?
    @IBOutlet weak var currentPrecipitationLabel: UILabel?

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.

        let baseURL = NSURL(string: "https://api.forecast.io/forecast/\(forecastAPIKey)/")
        let forecastURL = NSURL(string: "37.8267,-122.423", relativeToURL: baseURL)

        let weatherData = NSData(contentsOfFile: forecastURL!, options: nil, error: nil)
        //println(weatherData)


        /*if let plistPath = NSBundle.mainBundle().pathForResource("CurrentWeather", ofType: "plist"),
        let weatherDictionary = NSDictionary( contentsOfFile: plistPath),
        let currentWeatherDictionary = weatherDictionary["currently"] as? [String: AnyObject]
        {
            let currentWeather = CurrentWeather(weatherDictionary: currentWeatherDictionary)

            currentTemperatureLabel?.text = "\(currentWeather.temperature)"
            currentHumidityLabel?.text = "\(currentWeather.humidity) %"
            currentPrecipitationLabel?.text = "\(currentWeather.precipProbability)%"
        }*/

    }

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


}