How to parse/deserialize dynamic JSON

Scenario:
Consider the following is the JSON :

{
   "Bangalore_City": "35_Temperature",
   "NewYork_City": "31_Temperature",
   "Copenhagen_City": "29_Temperature"
}

If you notice, the data is structured in such a way that there is no hard-coded keys mentioning City / Temperature its basically just values.

Issue: I am not able to parse any JSON which is dynamic.

Question: Could anyone have found solution for this kind of JSON parsing? I tried go-simplejson, gabs & default encoding/json but no luck.

Note: The above JSON is just for sample. And there are lot of applications which are using the current API, So I do not want to change how the data is structured. I mean I can’t change to something as follows:

[{
   "City_Name":"Bangalore",
   "Temperature": "35"
},...]

Then I can define struct

type TempData struct {
  City_Name string
  Temperature  string
}