Edit in JSFiddle

angular.module('WeatherApp', [])

.controller('mainController', ['$scope', function($scope) {

  var self = this;

  self.currentWeather = {
    description: 'Moc hezky',
    temperature: 24,
    windSpeed: 20
  }

}])

.directive('weatherWidget', [function() {

  return {

    scope: {
      weatherData: '='
    },

    template: '<h2>Aktuální počasí: {{weatherData.description}}</h2>' +
      '<p>Je {{weatherData.temperature}} stupňů, s rychlostí větru {{weatherData.windSpeed}} m/s.</p>'

  }

}])
<div ng-app="WeatherApp" ng-controller="mainController as main">
  <weather-widget weather-data="main.currentWeather"></weather-widget>
</div>