diff --git a/src/main/java/com/github/prominence/openweathermap/api/OpenWeatherMapClient.java b/src/main/java/com/github/prominence/openweathermap/api/OpenWeatherMapClient.java
index 02134a0..fc94941 100644
--- a/src/main/java/com/github/prominence/openweathermap/api/OpenWeatherMapClient.java
+++ b/src/main/java/com/github/prominence/openweathermap/api/OpenWeatherMapClient.java
@@ -31,7 +31,6 @@ import com.github.prominence.openweathermap.api.request.weather.CurrentWeatherRe
 import static com.github.prominence.openweathermap.api.enums.SubscriptionPlan.*;
 
 public class OpenWeatherMapClient {
-
     private final String apiKey;
 
     public OpenWeatherMapClient(String apiKey) {
@@ -47,10 +46,4 @@ public class OpenWeatherMapClient {
     public FiveDayThreeHourStepForecastRequester forecast5Day3HourStep() {
         return new FiveDayThreeHourStepForecastRequesterImpl(apiKey);
     }
-
-    // TODO:
-    // * Forecast: hourly, daily. Probably better to cover all free-plan functionality?
-    // * Air Pollution
-    // * Ultraviolet index
-    // DOCS
 }
diff --git a/src/main/java/com/github/prominence/openweathermap/api/request/forecast/free/FiveDayThreeHourStepForecastRequester.java b/src/main/java/com/github/prominence/openweathermap/api/request/forecast/free/FiveDayThreeHourStepForecastRequester.java
index 7c36de1..9ac7d48 100644
--- a/src/main/java/com/github/prominence/openweathermap/api/request/forecast/free/FiveDayThreeHourStepForecastRequester.java
+++ b/src/main/java/com/github/prominence/openweathermap/api/request/forecast/free/FiveDayThreeHourStepForecastRequester.java
@@ -24,6 +24,9 @@ package com.github.prominence.openweathermap.api.request.forecast.free;
 
 import com.github.prominence.openweathermap.api.model.Coordinate;
 
+/**
+ * An interface for <a href="https://openweathermap.org/forecast5">API</a> methods.
+ */
 public interface FiveDayThreeHourStepForecastRequester {
 
     FiveDayThreeHourStepForecastRequestCustomizer byCityName(String cityName);
@@ -37,4 +40,6 @@ public interface FiveDayThreeHourStepForecastRequester {
     FiveDayThreeHourStepForecastRequestCustomizer byCoordinate(Coordinate coordinate);
 
     FiveDayThreeHourStepForecastRequestCustomizer byZipCodeAndCountry(String zipCode, String countryCode);
+
+    FiveDayThreeHourStepForecastRequestCustomizer byZipCodeInUSA(String zipCode);
 }
diff --git a/src/main/java/com/github/prominence/openweathermap/api/request/forecast/free/FiveDayThreeHourStepForecastRequesterImpl.java b/src/main/java/com/github/prominence/openweathermap/api/request/forecast/free/FiveDayThreeHourStepForecastRequesterImpl.java
index 2474b9b..863158b 100644
--- a/src/main/java/com/github/prominence/openweathermap/api/request/forecast/free/FiveDayThreeHourStepForecastRequesterImpl.java
+++ b/src/main/java/com/github/prominence/openweathermap/api/request/forecast/free/FiveDayThreeHourStepForecastRequesterImpl.java
@@ -70,4 +70,10 @@ public class FiveDayThreeHourStepForecastRequesterImpl implements FiveDayThreeHo
         urlBuilder.addRequestParameter("zip", zipCode + "," + countryCode);
         return new FiveDayThreeHourStepForecastRequestCustomizerImpl(urlBuilder);
     }
+
+    @Override
+    public FiveDayThreeHourStepForecastRequestCustomizer byZipCodeInUSA(String zipCode) {
+        urlBuilder.addRequestParameter("zip", zipCode);
+        return new FiveDayThreeHourStepForecastRequestCustomizerImpl(urlBuilder);
+    }
 }
diff --git a/src/main/java/com/github/prominence/openweathermap/api/request/weather/CurrentWeatherRequester.java b/src/main/java/com/github/prominence/openweathermap/api/request/weather/CurrentWeatherRequester.java
index 702f5ea..bb4b7e9 100644
--- a/src/main/java/com/github/prominence/openweathermap/api/request/weather/CurrentWeatherRequester.java
+++ b/src/main/java/com/github/prominence/openweathermap/api/request/weather/CurrentWeatherRequester.java
@@ -25,6 +25,9 @@ package com.github.prominence.openweathermap.api.request.weather;
 import com.github.prominence.openweathermap.api.request.weather.multiple.MultipleLocationsCurrentWeatherRequester;
 import com.github.prominence.openweathermap.api.request.weather.single.SingleLocationCurrentWeatherRequester;
 
+/**
+ * An interface for <a href="https://openweathermap.org/current">API</a> methods.
+ */
 public interface CurrentWeatherRequester {
 
     SingleLocationCurrentWeatherRequester single();
diff --git a/src/test/java/com/github/prominence/openweathermap/api/request/forecast/free/FiveDayThreeHourStepForecastIntegrationTest.java b/src/test/java/com/github/prominence/openweathermap/api/request/forecast/free/FiveDayThreeHourStepForecastIntegrationTest.java
index 0f0c56f..51ed656 100644
--- a/src/test/java/com/github/prominence/openweathermap/api/request/forecast/free/FiveDayThreeHourStepForecastIntegrationTest.java
+++ b/src/test/java/com/github/prominence/openweathermap/api/request/forecast/free/FiveDayThreeHourStepForecastIntegrationTest.java
@@ -23,16 +23,23 @@
 package com.github.prominence.openweathermap.api.request.forecast.free;
 
 import com.github.prominence.openweathermap.api.ApiTest;
+import com.github.prominence.openweathermap.api.OpenWeatherMapClient;
 import com.github.prominence.openweathermap.api.enums.Language;
 import com.github.prominence.openweathermap.api.enums.UnitSystem;
+import com.github.prominence.openweathermap.api.exception.InvalidAuthTokenException;
+import com.github.prominence.openweathermap.api.exception.NoDataFoundException;
+import com.github.prominence.openweathermap.api.model.Coordinate;
 import com.github.prominence.openweathermap.api.model.forecast.Forecast;
+import com.github.prominence.openweathermap.api.model.forecast.WeatherForecast;
 import org.junit.Assert;
 import org.junit.Test;
 
-public class FiveDayThreeHourStepForecastIntegrationTest extends ApiTest {
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
 
+public class FiveDayThreeHourStepForecastIntegrationTest extends ApiTest {
     @Test
-    public void whenGetJavaObject_thenReturnNotNull() {
+    public void whenGetForecastByCityNameRequestAsJava_thenReturnNotNull() {
         final Forecast forecast = getClient()
                 .forecast5Day3HourStep()
                 .byCityName("Minsk")
@@ -43,19 +50,421 @@ public class FiveDayThreeHourStepForecastIntegrationTest extends ApiTest {
                 .asJava();
 
         Assert.assertNotNull(forecast);
-        System.out.println(forecast);
+        Assert.assertNotNull(forecast.getLocation());
+        Assert.assertNotNull(forecast.getWeatherForecasts());
+        for (WeatherForecast weatherForecast : forecast.getWeatherForecasts()) {
+            Assert.assertNotNull(weatherForecast.getState());
+            Assert.assertNotNull(weatherForecast.getDescription());
+            Assert.assertNotNull(weatherForecast.getForecastTime());
+            Assert.assertNotNull(weatherForecast.getTemperature());
+            Assert.assertNotNull(weatherForecast.getAtmosphericPressure());
+            Assert.assertNotNull(weatherForecast.getHumidity());
+            Assert.assertNotNull(weatherForecast.getWind());
+        }
     }
 
     @Test
-    public void whenGetJavaObject_thenFieldsAreFilled() {
+    public void whenGetForecastByCityNameRequestAsJSON_thenReturnNotNull() {
+        final String forecastJson = getClient()
+                .forecast5Day3HourStep()
+                .byCityName("Minsk")
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .count(15)
+                .retrieve()
+                .asJSON();
+
+        Assert.assertTrue(forecastJson.startsWith("{"));
+    }
+
+    @Test
+    public void whenGetForecastByCityNameRequestAsXML_thenReturnNotNull() {
+        final String forecastXml = getClient()
+                .forecast5Day3HourStep()
+                .byCityName("Minsk")
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .count(15)
+                .retrieve()
+                .asXML();
+
+        Assert.assertTrue(forecastXml.startsWith("<"));
+    }
+
+    @Test
+    public void whenGetForecastByCityNameAndCountryCodeRequestAsJava_thenReturnNotNull() {
         final Forecast forecast = getClient()
                 .forecast5Day3HourStep()
-                .byCityName("London")
+                .byCityName("Minsk", "BY")
                 .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .count(15)
                 .retrieve()
                 .asJava();
 
         Assert.assertNotNull(forecast);
-        System.out.println(forecast);
+        Assert.assertNotNull(forecast.getLocation());
+        Assert.assertNotNull(forecast.getWeatherForecasts());
+        for (WeatherForecast weatherForecast : forecast.getWeatherForecasts()) {
+            Assert.assertNotNull(weatherForecast.getState());
+            Assert.assertNotNull(weatherForecast.getDescription());
+            Assert.assertNotNull(weatherForecast.getForecastTime());
+            Assert.assertNotNull(weatherForecast.getTemperature());
+            Assert.assertNotNull(weatherForecast.getAtmosphericPressure());
+            Assert.assertNotNull(weatherForecast.getHumidity());
+            Assert.assertNotNull(weatherForecast.getWind());
+        }
+    }
+
+    @Test
+    public void whenGetForecastByCityNameAndCountryCodeRequestAsJSON_thenReturnNotNull() {
+        final String forecastJson = getClient()
+                .forecast5Day3HourStep()
+                .byCityName("Minsk", "by")
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .count(15)
+                .retrieve()
+                .asJSON();
+
+        Assert.assertTrue(forecastJson.startsWith("{"));
+    }
+
+    @Test
+    public void whenGetForecastByCityNameAndCountryCodeRequestAsXML_thenReturnNotNull() {
+        final String forecastXml = getClient()
+                .forecast5Day3HourStep()
+                .byCityName("Minsk", "by")
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .count(15)
+                .retrieve()
+                .asXML();
+
+        Assert.assertTrue(forecastXml.startsWith("<"));
+    }
+
+    @Test
+    public void whenGetForecastByCityNameAndStateCodeAndCountryCodeRequestAsJava_thenReturnNotNull() {
+        final Forecast forecast = getClient()
+                .forecast5Day3HourStep()
+                .byCityName("New York", "NY", "US")
+                .language(Language.CHINESE_TRADITIONAL)
+                .unitSystem(UnitSystem.STANDARD)
+                .count(15)
+                .retrieve()
+                .asJava();
+
+        Assert.assertNotNull(forecast);
+        Assert.assertNotNull(forecast.getLocation());
+        Assert.assertNotNull(forecast.getWeatherForecasts());
+        for (WeatherForecast weatherForecast : forecast.getWeatherForecasts()) {
+            Assert.assertNotNull(weatherForecast.getState());
+            Assert.assertNotNull(weatherForecast.getDescription());
+            Assert.assertNotNull(weatherForecast.getForecastTime());
+            Assert.assertNotNull(weatherForecast.getTemperature());
+            Assert.assertNotNull(weatherForecast.getAtmosphericPressure());
+            Assert.assertNotNull(weatherForecast.getHumidity());
+            Assert.assertNotNull(weatherForecast.getWind());
+        }
+    }
+
+    @Test
+    public void whenGetForecastByCityNameAndStateCodeAndCountryCodeRequestAsJSON_thenReturnNotNull() {
+        final String forecastJson = getClient()
+                .forecast5Day3HourStep()
+                .byCityName("New York", "NY", "US")
+                .language(Language.SPANISH)
+                .unitSystem(UnitSystem.IMPERIAL)
+                .count(15)
+                .retrieve()
+                .asJSON();
+
+        Assert.assertTrue(forecastJson.startsWith("{"));
+    }
+
+    @Test
+    public void whenGetForecastByCityNameAndStateCodeAndCountryCodeRequestAsXML_thenReturnNotNull() {
+        final String forecastXml = getClient()
+                .forecast5Day3HourStep()
+                .byCityName("New York", "NY", "US")
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .retrieve()
+                .asXML();
+
+        Assert.assertTrue(forecastXml.startsWith("<"));
+    }
+
+    @Test
+    public void whenGetForecastByCityIdRequestAsJava_thenReturnNotNull() {
+        final Forecast forecast = getClient()
+                .forecast5Day3HourStep()
+                .byCityId(350001514)
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .count(15)
+                .retrieve()
+                .asJava();
+
+        Assert.assertNotNull(forecast);
+        Assert.assertNotNull(forecast.getLocation());
+        Assert.assertNotNull(forecast.getWeatherForecasts());
+        for (WeatherForecast weatherForecast : forecast.getWeatherForecasts()) {
+            Assert.assertNotNull(weatherForecast.getState());
+            Assert.assertNotNull(weatherForecast.getDescription());
+            Assert.assertNotNull(weatherForecast.getForecastTime());
+            Assert.assertNotNull(weatherForecast.getTemperature());
+            Assert.assertNotNull(weatherForecast.getAtmosphericPressure());
+            Assert.assertNotNull(weatherForecast.getHumidity());
+            Assert.assertNotNull(weatherForecast.getWind());
+        }
+    }
+
+    @Test
+    public void whenGetForecastByCityIdRequestAsJSON_thenReturnNotNull() {
+        final String forecastJson = getClient()
+                .forecast5Day3HourStep()
+                .byCityId(350001514)
+                .language(Language.SPANISH)
+                .unitSystem(UnitSystem.IMPERIAL)
+                .count(15)
+                .retrieve()
+                .asJSON();
+
+        Assert.assertTrue(forecastJson.startsWith("{"));
+    }
+
+    @Test
+    public void whenGetForecastByCityIdRequestAsXML_thenReturnNotNull() {
+        final String forecastXml = getClient()
+                .forecast5Day3HourStep()
+                .byCityId(350001514)
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .retrieve()
+                .asXML();
+
+        Assert.assertTrue(forecastXml.startsWith("<"));
+    }
+
+    @Test
+    public void whenGetForecastByCoordinatesRequestAsJava_thenReturnNotNull() {
+        final Forecast forecast = getClient()
+                .forecast5Day3HourStep()
+                .byCoordinate(Coordinate.forValues(5, 5))
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .count(15)
+                .retrieve()
+                .asJava();
+
+        Assert.assertNotNull(forecast);
+        Assert.assertNotNull(forecast.getLocation());
+        Assert.assertNotNull(forecast.getWeatherForecasts());
+        for (WeatherForecast weatherForecast : forecast.getWeatherForecasts()) {
+            Assert.assertNotNull(weatherForecast.getState());
+            Assert.assertNotNull(weatherForecast.getDescription());
+            Assert.assertNotNull(weatherForecast.getForecastTime());
+            Assert.assertNotNull(weatherForecast.getTemperature());
+            Assert.assertNotNull(weatherForecast.getAtmosphericPressure());
+            Assert.assertNotNull(weatherForecast.getHumidity());
+            Assert.assertNotNull(weatherForecast.getWind());
+        }
+    }
+
+    @Test
+    public void whenGetForecastByCoordinatesRequestAsJSON_thenReturnNotNull() {
+        final String forecastJson = getClient()
+                .forecast5Day3HourStep()
+                .byCoordinate(Coordinate.forValues(5, 5))
+                .language(Language.SPANISH)
+                .unitSystem(UnitSystem.IMPERIAL)
+                .count(15)
+                .retrieve()
+                .asJSON();
+
+        Assert.assertTrue(forecastJson.startsWith("{"));
+    }
+
+    @Test
+    public void whenGetForecastByCoordinatesRequestAsXML_thenReturnNotNull() {
+        final String forecastXml = getClient()
+                .forecast5Day3HourStep()
+                .byCoordinate(Coordinate.forValues(5, 5))
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .retrieve()
+                .asXML();
+
+        Assert.assertTrue(forecastXml.startsWith("<"));
+    }
+
+    @Test
+    public void whenGetForecastByZipCodeInUSARequestAsJava_thenReturnNotNull() {
+        final Forecast forecast = getClient()
+                .forecast5Day3HourStep()
+                .byZipCodeInUSA("10005")
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .count(15)
+                .retrieve()
+                .asJava();
+
+        Assert.assertNotNull(forecast);
+        Assert.assertNotNull(forecast.getLocation());
+        Assert.assertNotNull(forecast.getWeatherForecasts());
+        for (WeatherForecast weatherForecast : forecast.getWeatherForecasts()) {
+            Assert.assertNotNull(weatherForecast.getState());
+            Assert.assertNotNull(weatherForecast.getDescription());
+            Assert.assertNotNull(weatherForecast.getForecastTime());
+            Assert.assertNotNull(weatherForecast.getTemperature());
+            Assert.assertNotNull(weatherForecast.getAtmosphericPressure());
+            Assert.assertNotNull(weatherForecast.getHumidity());
+            Assert.assertNotNull(weatherForecast.getWind());
+        }
+    }
+
+    @Test
+    public void whenGetForecastByZipCodeInUSARequestAsJSON_thenReturnNotNull() {
+        final String forecastJson = getClient()
+                .forecast5Day3HourStep()
+                .byZipCodeInUSA("10005")
+                .language(Language.SPANISH)
+                .unitSystem(UnitSystem.IMPERIAL)
+                .count(15)
+                .retrieve()
+                .asJSON();
+
+        Assert.assertTrue(forecastJson.startsWith("{"));
+    }
+
+    @Test
+    public void whenGetForecastByZipCodeInUSARequestAsXML_thenReturnNotNull() {
+        final String forecastXml = getClient()
+                .forecast5Day3HourStep()
+                .byZipCodeInUSA("10005")
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .retrieve()
+                .asXML();
+
+        Assert.assertTrue(forecastXml.startsWith("<"));
+    }
+
+    @Test
+    public void whenGetForecastByZipCodeAndCountryCodeRequestAsJava_thenReturnNotNull() {
+        final Forecast forecast = getClient()
+                .forecast5Day3HourStep()
+                .byZipCodeAndCountry("220015", "by")
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .count(15)
+                .retrieve()
+                .asJava();
+
+        Assert.assertNotNull(forecast);
+        Assert.assertNotNull(forecast.getLocation());
+        Assert.assertNotNull(forecast.getWeatherForecasts());
+        for (WeatherForecast weatherForecast : forecast.getWeatherForecasts()) {
+            Assert.assertNotNull(weatherForecast.getState());
+            Assert.assertNotNull(weatherForecast.getDescription());
+            Assert.assertNotNull(weatherForecast.getForecastTime());
+            Assert.assertNotNull(weatherForecast.getTemperature());
+            Assert.assertNotNull(weatherForecast.getAtmosphericPressure());
+            Assert.assertNotNull(weatherForecast.getHumidity());
+            Assert.assertNotNull(weatherForecast.getWind());
+        }
+    }
+
+    @Test
+    public void whenGetForecastByZipCodeAndCountryCodeRequestAsJSON_thenReturnNotNull() {
+        final String forecastJson = getClient()
+                .forecast5Day3HourStep()
+                .byZipCodeAndCountry("220015", "by")
+                .language(Language.SPANISH)
+                .unitSystem(UnitSystem.IMPERIAL)
+                .count(15)
+                .retrieve()
+                .asJSON();
+
+        Assert.assertTrue(forecastJson.startsWith("{"));
+    }
+
+    @Test
+    public void whenGetForecastByZipCodeAndCountryCodeRequestAsXML_thenReturnNotNull() {
+        final String forecastXml = getClient()
+                .forecast5Day3HourStep()
+                .byZipCodeAndCountry("220015", "by")
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .retrieve()
+                .asXML();
+
+        Assert.assertTrue(forecastXml.startsWith("<"));
+    }
+
+    @Test
+    public void whenGetForecastByCityNameAsyncRequestAsJava_thenReturnNotNull() throws ExecutionException, InterruptedException {
+        final CompletableFuture<Forecast> forecastFuture = getClient()
+                .forecast5Day3HourStep()
+                .byCityName("Minsk")
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .count(15)
+                .retrieveAsync()
+                .asJava();
+
+        Assert.assertNotNull(forecastFuture);
+        System.out.println(forecastFuture.get());
+    }
+
+    @Test
+    public void whenGetForecastByCityNameAsyncRequestAsJSON_thenReturnNotNull() throws ExecutionException, InterruptedException {
+        final CompletableFuture<String> forecastFuture = getClient()
+                .forecast5Day3HourStep()
+                .byCityId(350001514)
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .count(15)
+                .retrieveAsync()
+                .asJSON();
+
+        Assert.assertNotNull(forecastFuture);
+        System.out.println(forecastFuture.get());
+    }
+
+    @Test
+    public void whenGetForecastByCityNameAsyncRequestAsXML_thenReturnNotNull() throws ExecutionException, InterruptedException {
+        final CompletableFuture<String> forecastFuture = getClient()
+                .forecast5Day3HourStep()
+                .byCityId(350001514)
+                .language(Language.ENGLISH)
+                .unitSystem(UnitSystem.METRIC)
+                .count(15)
+                .retrieveAsync()
+                .asXML();
+
+        Assert.assertNotNull(forecastFuture);
+        System.out.println(forecastFuture.get());
+    }
+
+    @Test(expected = InvalidAuthTokenException.class)
+    public void whenRequestCurrentWeatherWithInvalidApiKey_thenThrowAnException() {
+        OpenWeatherMapClient client = new OpenWeatherMapClient("invalidKey");
+        client
+                .forecast5Day3HourStep()
+                .byCityId(350001514)
+                .retrieve()
+                .asJSON();
+    }
+
+    @Test(expected = NoDataFoundException.class)
+    public void whenRequestCurrentWeatherForInvalidLocation_thenThrowAnException() {
+        getClient()
+                .forecast5Day3HourStep()
+                .byCityName("invalidCity")
+                .retrieve()
+                .asJava();
     }
 }