Can't get json from weather-api. iOS

Question

Here is JSON file

 {
  "weather":[  
    {  
     "id":804,
     "main":"Clouds",
     "description":"overcast clouds",
     "icon":"04d"
  }
],
 "main":{  
  "temp":273.15,
  "pressure":1035,
  "humidity":84,
  "temp_min":273.15,
  "temp_max":273.15
},

"name":"Wroclaw",

 }

Here is code.

var cityName: String!
var degree: Int!
var someWeather: String!

let json = try JSONSerialization.jsonObject(with: data!, options: .mutableContainers) as! [String : AnyObject]


            if let main = json["main"] as? [String : AnyObject] {
                if let temp = main["temp"] as? Int {
                    self.degree = temp
                }
            }
            if let city = json["name"] as? String {
                self.cityName = city
            }
}

     if let weather = json["weather"] as? [String : AnyObject] {
     if let someWeather = weather["main"] as? String {
     self.weatherDescription = someWeather 
} 
} 

labelWeather.text = self.weatherDescription

How to save to variable weatherDescription the value of "main" or "description" from weather in json? I try like in this code, but it doesn't show me anything . Degrees and city name works correct and shows, but weather doesn't work.

Updated code //////////////////////////////////////

  var  let json = try JSONSerialization.jsonObject(with: data!, options: .mutableContainers) as! [String : AnyObject]


                if let main = json["main"] as? [String : AnyObject] {
                    if let temp = main["temp"] as? Int {
                        self.degree = temp
                    }
                    if let pressuer = main["pressure"] as? Int {
                        self.cisnienie = pressuer
                    }
                }

                if let weather = json["weather"] as? [[String : Any]] {
                    for data in weather {
                        if let main = data["main"] as? String {
                            print(main)
                        }
                    }
                }

                if let nazwa = json["name"] as? String {
                    self.nazwaMiasta = nazwa
                }

Here is all JSON file:

{  
   "coord":{  
      "lon":-0.13,
      "lat":51.51
   },
   "weather":[  
      {  
         "id":800,
         "main":"Clear",
         "description":"clear sky",
         "icon":"01d"
      }
  ],
  "base":"stations",
  "main":{  
     "temp":279.07,
     "pressure":1032,
     "humidity":52,
     "temp_min":278.15,
     "temp_max":280.15
  },
    "visibility":10000,
     "wind":{  
     "speed":7.2,
     "deg":80
  },
   "clouds":{  
    "all":0
 },
  "dt":1484923800,
 "sys":{  
     "type":1,
     "id":5091,
     "message":0.0087,
     "country":"GB",
     "sunrise":1484898825,
     "sunset":1484929819
  },
  "id":2643743,
  "name":"London",
  "cod":200
}

Answer 1

"weather" is an array not dictionary ..

if let weather = json["weather"] as? [[String : Any]] {
    for data in weather{
       if let main = data["main"] as? String{
           print(main)
       }
    }
}