diff --git a/observer/README.md b/observer/README.md
index caaaf5d..29c8b86 100644
--- a/observer/README.md
+++ b/observer/README.md
@@ -1,3 +1,12 @@
 # Наблюдатель
 
 Наблюдатель — это поведенческий паттерн проектирования, который создаёт механизм подписки, позволяющий одним объектам следить и реагировать на события, происходящие в других объектах.
+
+При использовании паттерна возможен как запрос, так и активная доставка данных от субъекта (запрос считается более "правильным").
+
+- **Активная доставка** - передача субъектом аргументов в качестве параметров функции `update()`
+- **Запрос** - подразумевает получение необходимых параметров от субъекта внутри функции `update()`
+
+## Принципы
+
+- Стремиться к слабой связанности взаимодействующих объектов
diff --git a/observer/app.d b/observer/app.d
index 9b44bc3..3db78f5 100644
--- a/observer/app.d
+++ b/observer/app.d
@@ -1,17 +1,22 @@
 module observer.app;
+
 import observer.weatherdata;
 import observer.currentconditionsdisplay;
 import observer.heatindexdisplay;
+import observer.forecastdisplay;
+import observer.statiscticdisplay;
 
 void main()
 {
     WeatherData weatherData = new WeatherData();
     CurrentConditionsDisplay currentDisplay = new CurrentConditionsDisplay(weatherData);
     HeatIndexDisplay heatIndexDisplay = new HeatIndexDisplay(weatherData);
+    ForecastDisplay forecastDisplay = new ForecastDisplay(weatherData);
+    StatisticsDisplay statisticsDisplay = new StatisticsDisplay(weatherData);
 
     weatherData.setMeasurements(80, 65, 30.4f);
     weatherData.setMeasurements(82, 70, 29.2f);
-    weatherData.removeObserver(heatIndexDisplay);
+    weatherData.removeObserver(forecastDisplay);
     weatherData.setMeasurements(78, 90, 29.2f);
     weatherData.setMeasurements(81, 72, 29.5f);
 }
diff --git a/observer/currentconditionsdisplay.d b/observer/currentconditionsdisplay.d
index 815d082..aaec318 100644
--- a/observer/currentconditionsdisplay.d
+++ b/observer/currentconditionsdisplay.d
@@ -1,4 +1,5 @@
 module observer.currentconditionsdisplay;
+
 import observer.displayelement;
 import observer.observer;
 import observer.weatherdata;
@@ -14,13 +15,14 @@ private:
 public:
     this(WeatherData weatherData)
     {
+        this.weatherData = weatherData;
         weatherData.registerObserver(this);
     }
 
-    override void update(float temperature, float humidity, float pressure)
+    override void update()
     {
-        this.temperature = temperature;
-        this.humidity = humidity;
+        this.temperature = weatherData.getTemperature;
+        this.humidity = weatherData.getHumidity;
         display();
     }
 
diff --git a/observer/forecastdisplay.d b/observer/forecastdisplay.d
new file mode 100644
index 0000000..9840471
--- /dev/null
+++ b/observer/forecastdisplay.d
@@ -0,0 +1,40 @@
+module observer.forecastdisplay;
+
+import observer.displayelement;
+import observer.observer;
+import observer.weatherdata;
+import std.stdio : write, writeln;
+import std.format : format;
+
+class ForecastDisplay : Observer, DisplayElement
+{
+private:
+    float currentPressure = 29.92f;
+    float lastPressure;
+    WeatherData weatherData;
+public:
+    this(WeatherData weatherData)
+    {
+        this.weatherData = weatherData;
+        weatherData.registerObserver(this);
+    }
+
+    override void update()
+    {
+        lastPressure = currentPressure;
+        currentPressure = weatherData.getPressure;
+        display();
+    }
+
+    override void display()
+    {
+        write("Forecast: ");
+        if (currentPressure > lastPressure) {
+			writeln("Improving weather on the way!");
+		} else if (currentPressure == lastPressure) {
+			writeln("More of the same");
+		} else if (currentPressure < lastPressure) {
+			writeln("Watch out for cooler, rainy weather");
+		}
+    }
+}
diff --git a/observer/heatindexdisplay.d b/observer/heatindexdisplay.d
index eedc621..ac98ee8 100644
--- a/observer/heatindexdisplay.d
+++ b/observer/heatindexdisplay.d
@@ -1,4 +1,5 @@
 module observer.heatindexdisplay;
+
 import observer.displayelement;
 import observer.observer;
 import observer.weatherdata;
@@ -22,12 +23,13 @@ private:
 public:
     this(WeatherData weatherData)
     {
+        this.weatherData = weatherData;
         weatherData.registerObserver(this);
     }
 
-    override void update(float temperature, float humidity, float pressure)
+    override void update()
     {
-        this.heatIndex = computeHeatIndex(temperature, humidity);
+        this.heatIndex = computeHeatIndex(weatherData.getTemperature, weatherData.getHumidity);
         display();
     }
 
diff --git a/observer/observer.d b/observer/observer.d
index a4e5e08..8665f4d 100644
--- a/observer/observer.d
+++ b/observer/observer.d
@@ -2,5 +2,5 @@ module observer.observer;
 
 interface Observer
 {
-    void update(float temp, float humidity, float pressure);
+    void update();
 }
diff --git a/observer/statiscticdisplay.d b/observer/statiscticdisplay.d
new file mode 100644
index 0000000..55e7601
--- /dev/null
+++ b/observer/statiscticdisplay.d
@@ -0,0 +1,47 @@
+module observer.statiscticdisplay;
+
+import observer.displayelement;
+import observer.observer;
+import observer.weatherdata;
+import std.stdio : writeln;
+import std.format : format;
+
+class StatisticsDisplay : Observer, DisplayElement
+{
+private:
+    float maxTemp = 0.0f;
+    float minTemp = 200;
+    float tempSum= 0.0f;
+    int numReadings;
+    WeatherData weatherData;
+public:
+    this(WeatherData weatherData)
+    {
+        this.weatherData = weatherData;
+        weatherData.registerObserver(this);
+    }
+
+    override void update()
+    {
+        tempSum += weatherData.getTemperature;
+        numReadings++;
+
+        if (weatherData.getTemperature > maxTemp)
+        {
+            maxTemp = weatherData.getTemperature;
+        }
+
+        if (weatherData.getTemperature < minTemp)
+        {
+            minTemp = weatherData.getTemperature;
+        }
+
+        display();
+    }
+
+    override void display()
+    {
+        writeln("Avg/Max/Min temperature = ", (tempSum / numReadings), '/', maxTemp, '/', minTemp);
+        // writeln("Avg/Max/Min temperature = ".format(temperature), "F degrees and %3.1f%% humidity".format(humidity));
+    }
+}
diff --git a/observer/subject.d b/observer/subject.d
index 668feb0..8fa85b1 100644
--- a/observer/subject.d
+++ b/observer/subject.d
@@ -1,4 +1,5 @@
 module observer.subject;
+
 import observer.observer;
 
 interface Subject
diff --git a/observer/weatherdata.d b/observer/weatherdata.d
index 4029c45..9970d1b 100644
--- a/observer/weatherdata.d
+++ b/observer/weatherdata.d
@@ -1,4 +1,5 @@
 module observer.weatherdata;
+
 import observer.subject;
 import observer.observer;
 import std.algorithm : remove, countUntil;
@@ -25,7 +26,7 @@ public:
     {
         foreach (Observer o; observers)
         {
-            o.update(temperature, humidity, pressure);
+            o.update();
         }
     }