anchor.diff:                  "observedUntil": "2016-10-15T08:00:00Z",
                   "observedPeriod": "PT3H",
                   "pressureChangeInHectoPascal": 2,
  -                "pressureTendencyCode": 1
  +                "pressureTendencyCode": 1,
  +                "precipitationAmountInMillimeter": 1.2,
  +                "precipitationAmountInInch": 0.047
  +              },
  +              {
  +                "locatedAt": [ -2.2323, 47.4593 ],
  +                "meteoGroupStationId": "3007237",
  +                "meteoGroupStationName": "Pleucadeuc",
  +                "stationLocation": [ -2.2323, 47.4593 ],
  +                "stationTimeZoneName": "Europe/Prague",
  +                "observedFrom": "2016-10-15T02:00:00Z",
  +                "observedUntil": "2016-10-15T08:00:00Z",
  +                "observedPeriod": "PT6H",
  +                "precipitationAmountInMillimeter": 1.4,
  +                "precipitationAmountInInch": 0.055
                 },
                 {
                   "locatedAt": [ -2.2323, 47.4593 ],
  
positive.code:                 visibilityInNauticalMile,visibilityInStatuteMile, weatherCode, weatherCodeTraditional
  - **PT1H** -    windGustInMeterPerSecond, windGustInKilometerPerHour, windGustInMilesPerHour, windGustInBeaufort, windGustInKnots, precipitationAmountInMillimeter,
                  precipitationAmountInInch
  - **PT3H** -    pressureTendencyCode, pressureChangeInHectoPascal
  - **PT12H** -   temperatureMaxInCelsius, temperatureMaxInFahrenheit, temperatureMaxInKelvin, temperatureMinInCelsius, temperatureMinInFahrenheit, temperatureMinInKelvin
  - **PT24H** -   precipitationAmountInMillimeter, precipitationAmountInInch, sunshineDurationInHours, sunshineDurationInMinutes
  
  The "weatherCode" parameter refers to the WMO code table "0 20 003 - Present weather".
  
negative.code:                 "windGustInMilesPerHour": 1.8412471,
                  "windGustInBeaufort": 1,
                  "windGustInKnots": 1.5999997,
                  "precipitationAmountInMillimeter": 0.7,
                  "precipitationAmountInInch": 0.028
                },
                {
                  "locatedAt": [ -2.2323, 47.4593 ],
  