diff --git a/apps/openmw_tests/CMakeLists.txt b/apps/openmw_tests/CMakeLists.txt
index 9b57113110..5cfee9ce4b 100644
--- a/apps/openmw_tests/CMakeLists.txt
+++ b/apps/openmw_tests/CMakeLists.txt
@@ -10,6 +10,7 @@ file(GLOB UNITTEST_SRC_FILES
     mwworld/testduration.cpp
     mwworld/testtimestamp.cpp
     mwworld/testptr.cpp
+    mwworld/testweather.cpp
 
     mwdialogue/test_keywordsearch.cpp
 
diff --git a/apps/openmw_tests/mwworld/testweather.cpp b/apps/openmw_tests/mwworld/testweather.cpp
new file mode 100644
index 0000000000..2f51ad48e1
--- /dev/null
+++ b/apps/openmw_tests/mwworld/testweather.cpp
@@ -0,0 +1,739 @@
+#include <gtest/gtest.h>
+
+#include <cmath>
+
+#include "apps/openmw/mwworld/timestamp.hpp"
+#include "apps/openmw/mwworld/weather.hpp"
+
+namespace MWWorld
+{
+    namespace
+    {
+        // MASSER PHASES
+
+        TEST(MWWorldWeatherTest, masserPhasesFullToWaningGibbousAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 2 and 26, 11:57
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 2 + 11.0f + 56.0f / 60.0f);
+            timeStampAfter += (24.0f * 2 + 11.0f + 58.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 26 + 11.0f + 56.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 26 + 11.0f + 58.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+        }
+
+        TEST(MWWorldWeatherTest, masserPhasesWaningGibbousToThirdQuarterAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 5 and 29, 0:00
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 4 + 23.0f + 59.0f / 60.0f);
+            timeStampAfter += (24.0f * 5 + 0.0f + 1.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 28 + 23.0f + 59.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 29 + 0.0f + 1.0f / 60.0f);
+
+            MWWorld::MoonModel moon
+                = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish, axisOffset,
+                    speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+        }
+
+        TEST(MWWorldWeatherTest, masserPhasesThirdQuarterToWaningCrescentAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 8 and 32, 0:00
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 7 + 23.0f + 59.0f / 60.0f);
+            timeStampAfter += (24.0f * 8 + 0.0f + 1.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 31 + 23.0f + 59.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 32 + 0.0f + 1.0f / 60.0f);
+
+            MWWorld::MoonModel moon
+                = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish, axisOffset,
+                    speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+        }
+
+        TEST(MWWorldWeatherTest, masserPhasesWaningCrescentToNewAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 11 and 35, 0:00
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 10 + 23.0f + 59.0f / 60.0f);
+            timeStampAfter += (24.0f * 11 + 0.0f + 1.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 34 + 23.0f + 59.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 35 + 0.0f + 1.0f / 60.0f);
+
+            MWWorld::MoonModel moon
+                = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish, axisOffset,
+                    speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+        }
+
+        TEST(MWWorldWeatherTest, masserPhasesNewToWaxingCrescentAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 14 and 38, 0:00
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 13 + 23.0f + 59.0f / 60.0f);
+            timeStampAfter += (24.0f * 14 + 0.0f + 1.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 37 + 23.0f + 59.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 38 + 0.0f + 1.0f / 60.0f);
+
+            MWWorld::MoonModel moon
+                = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish, axisOffset,
+                    speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+        }
+
+        TEST(MWWorldWeatherTest, masserPhasesWaxingCrescentToFirstQuarterAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 17 and 41, 2:57
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 17 + 2.0f + 56.0f / 60.0f);
+            timeStampAfter += (24.0f * 17 + 2.0f + 58.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 41 + 2.0f + 56.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 41 + 2.0f + 58.0f / 60.0f);
+
+            MWWorld::MoonModel moon
+                = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish, axisOffset,
+                    speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+        }
+
+        TEST(MWWorldWeatherTest, masserPhasesFirstQuarterToWaxingGibbousAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 20 and 44, 5:57
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 20 + 5.0f + 56.0f / 60.0f);
+            timeStampAfter += (24.0f * 20 + 5.0f + 58.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 44 + 5.0f + 56.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 44 + 5.0f + 58.0f / 60.0f);
+
+            MWWorld::MoonModel moon
+                = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish, axisOffset,
+                    speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+        }
+
+        TEST(MWWorldWeatherTest, masserPhasesWaxingGibbousToFullAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 23 and 47, 8:57
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 23 + 8.0f + 56.0f / 60.0f);
+            timeStampAfter += (24.0f * 23 + 8.0f + 58.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 47 + 8.0f + 56.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 47 + 8.0f + 58.0f / 60.0f);
+
+            MWWorld::MoonModel moon
+                = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish, axisOffset,
+                    speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+        }
+    }
+
+    // SECUNDA PHASES
+
+        TEST(MWWorldWeatherTest, secundaPhasesFullToWaningGibbousAtCorrectTimes)
+    {
+        float dailyIncrement = 1.2f;
+        float speed = 0.6f;
+        float fadeEndAngle = 30.0f;
+        float fadeStartAngle = 50.0f;
+        float moonShadowEarlyFadeAngle = 0.5f;
+        float fadeInStart = 14.0f;
+        float fadeInFinish = 15.0f;
+        float fadeOutStart = 7.0f;
+        float fadeOutFinish = 10.0f;
+        float axisOffset = 50.0f;
+
+        // Days 2 and 26, 14:19
+        TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+        timeStampBefore += (24.0f * 2 + 14.0f + 18.0f / 60.0f);
+        timeStampAfter += (24.0f * 2 + 14.0f + 20.0f / 60.0f);
+        timeStampBeforePostLoop += (24.0f * 26 + 14.0f + 18.0f / 60.0f);
+        timeStampAfterPostLoop += (24.0f * 26 + 14.0f + 20.0f / 60.0f);
+
+        MWWorld::MoonModel moon = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+            axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+        MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+        MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+        MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+        MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+        EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+        EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+        EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+        EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+    }
+
+    TEST(MWWorldWeatherTest, secundaPhasesWaningGibbousToThirdQuarterAtCorrectTimes)
+    {
+        float dailyIncrement = 1.2f;
+        float speed = 0.6f;
+        float fadeEndAngle = 30.0f;
+        float fadeStartAngle = 50.0f;
+        float moonShadowEarlyFadeAngle = 0.5f;
+        float fadeInStart = 14.0f;
+        float fadeInFinish = 15.0f;
+        float fadeOutStart = 7.0f;
+        float fadeOutFinish = 10.0f;
+        float axisOffset = 50.0f;
+
+        // Days 5 and 29, 0:00
+        TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+        timeStampBefore += (24.0f * 4 + 23.0f + 59.0f / 60.0f);
+        timeStampAfter += (24.0f * 5 + 0.0f + 1.0f / 60.0f);
+        timeStampBeforePostLoop += (24.0f * 28 + 23.0f + 59.0f / 60.0f);
+        timeStampAfterPostLoop += (24.0f * 29 + 0.0f + 1.0f / 60.0f);
+
+        MWWorld::MoonModel moon = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+            axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+        MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+        MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+        MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+        MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+        EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+        EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+        EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+        EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+    }
+
+    TEST(MWWorldWeatherTest, secundaPhasesThirdQuarterToWaningCrescentAtCorrectTimes)
+    {
+        float dailyIncrement = 1.2f;
+        float speed = 0.6f;
+        float fadeEndAngle = 30.0f;
+        float fadeStartAngle = 50.0f;
+        float moonShadowEarlyFadeAngle = 0.5f;
+        float fadeInStart = 14.0f;
+        float fadeInFinish = 15.0f;
+        float fadeOutStart = 7.0f;
+        float fadeOutFinish = 10.0f;
+        float axisOffset = 50.0f;
+
+        // Days 8 and 32, 0:00
+        TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+        timeStampBefore += (24.0f * 7 + 23.0f + 59.0f / 60.0f);
+        timeStampAfter += (24.0f * 8 + 0.0f + 1.0f / 60.0f);
+        timeStampBeforePostLoop += (24.0f * 31 + 23.0f + 59.0f / 60.0f);
+        timeStampAfterPostLoop += (24.0f * 32 + 0.0f + 1.0f / 60.0f);
+
+        MWWorld::MoonModel moon = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+            axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+        MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+        MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+        MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+        MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+        EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+        EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+        EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+        EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+    }
+
+    TEST(MWWorldWeatherTest, secundaPhasesWaningCrescentToNewAtCorrectTimes)
+    {
+        float dailyIncrement = 1.2f;
+        float speed = 0.6f;
+        float fadeEndAngle = 30.0f;
+        float fadeStartAngle = 50.0f;
+        float moonShadowEarlyFadeAngle = 0.5f;
+        float fadeInStart = 14.0f;
+        float fadeInFinish = 15.0f;
+        float fadeOutStart = 7.0f;
+        float fadeOutFinish = 10.0f;
+        float axisOffset = 50.0f;
+
+        // Days 11 and 35, 0:00
+        TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+        timeStampBefore += (24.0f * 10 + 23.0f + 59.0f / 60.0f);
+        timeStampAfter += (24.0f * 11 + 0.0f + 1.0f / 60.0f);
+        timeStampBeforePostLoop += (24.0f * 34 + 23.0f + 59.0f / 60.0f);
+        timeStampAfterPostLoop += (24.0f * 35 + 0.0f + 1.0f / 60.0f);
+
+        MWWorld::MoonModel moon = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+            axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+        MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+        MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+        MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+        MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+        EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+        EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+        EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+        EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+    }
+
+    TEST(MWWorldWeatherTest, secundaPhasesNewToWaxingCrescentAtCorrectTimes)
+    {
+        float dailyIncrement = 1.2f;
+        float speed = 0.6f;
+        float fadeEndAngle = 30.0f;
+        float fadeStartAngle = 50.0f;
+        float moonShadowEarlyFadeAngle = 0.5f;
+        float fadeInStart = 14.0f;
+        float fadeInFinish = 15.0f;
+        float fadeOutStart = 7.0f;
+        float fadeOutFinish = 10.0f;
+        float axisOffset = 50.0f;
+
+        // Days 14 and 38, 0:00
+        TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+        timeStampBefore += (24.0f * 13 + 23.0f + 59.0f / 60.0f);
+        timeStampAfter += (24.0f * 14 + 0.0f + 1.0f / 60.0f);
+        timeStampBeforePostLoop += (24.0f * 37 + 23.0f + 59.0f / 60.0f);
+        timeStampAfterPostLoop += (24.0f * 38 + 0.0f + 1.0f / 60.0f);
+
+        MWWorld::MoonModel moon = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+            axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+        MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+        MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+        MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+        MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+        EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+        EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+        EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+        EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+    }
+
+    TEST(MWWorldWeatherTest, secundaPhasesWaxingCrescentToFirstQuarterAtCorrectTimes)
+    {
+        float dailyIncrement = 1.2f;
+        float speed = 0.6f;
+        float fadeEndAngle = 30.0f;
+        float fadeStartAngle = 50.0f;
+        float moonShadowEarlyFadeAngle = 0.5f;
+        float fadeInStart = 14.0f;
+        float fadeInFinish = 15.0f;
+        float fadeOutStart = 7.0f;
+        float fadeOutFinish = 10.0f;
+        float axisOffset = 50.0f;
+
+        // Days 17 and 41, 3:31
+        TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+        timeStampBefore += (24.0f * 17 + 3.0f + 30.0f / 60.0f);
+        timeStampAfter += (24.0f * 17 + 3.0f + 32.0f / 60.0f);
+        timeStampBeforePostLoop += (24.0f * 41 + 3.0f + 30.0f / 60.0f);
+        timeStampAfterPostLoop += (24.0f * 41 + 3.0f + 32.0f / 60.0f);
+
+        MWWorld::MoonModel moon = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+            axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+        MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+        MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+        MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+        MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+        EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+        EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+        EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+        EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+    }
+
+    TEST(MWWorldWeatherTest, secundaPhasesFirstQuarterToWaxingGibbousAtCorrectTimes)
+    {
+        float dailyIncrement = 1.2f;
+        float speed = 0.6f;
+        float fadeEndAngle = 30.0f;
+        float fadeStartAngle = 50.0f;
+        float moonShadowEarlyFadeAngle = 0.5f;
+        float fadeInStart = 14.0f;
+        float fadeInFinish = 15.0f;
+        float fadeOutStart = 7.0f;
+        float fadeOutFinish = 10.0f;
+        float axisOffset = 50.0f;
+
+        // Days 20 and 44, 7:07
+        TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+        timeStampBefore += (24.0f * 20 + 7.0f + 6.0f / 60.0f);
+        timeStampAfter += (24.0f * 20 + 7.0f + 8.0f / 60.0f);
+        timeStampBeforePostLoop += (24.0f * 44 + 7.0f + 6.0f / 60.0f);
+        timeStampAfterPostLoop += (24.0f * 44 + 7.0f + 8.0f / 60.0f);
+
+        MWWorld::MoonModel moon = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+            axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+        MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+        MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+        MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+        MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+        EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+        EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+        EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+        EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+    }
+
+    TEST(MWWorldWeatherTest, secundaPhasesWaxingGibbousToFullAtCorrectTimes)
+    {
+        float dailyIncrement = 1.2f;
+        float speed = 0.6f;
+        float fadeEndAngle = 30.0f;
+        float fadeStartAngle = 50.0f;
+        float moonShadowEarlyFadeAngle = 0.5f;
+        float fadeInStart = 14.0f;
+        float fadeInFinish = 15.0f;
+        float fadeOutStart = 7.0f;
+        float fadeOutFinish = 10.0f;
+        float axisOffset = 50.0f;
+
+        // Days 23 and 47, 10:43
+        TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+        timeStampBefore += (24.0f * 23 + 10.0f + 42.0f / 60.0f);
+        timeStampAfter += (24.0f * 23 + 10.0f + 44.0f / 60.0f);
+        timeStampBeforePostLoop += (24.0f * 47 + 10.0f + 42.0f / 60.0f);
+        timeStampAfterPostLoop += (24.0f * 47 + 10.0f + 44.0f / 60.0f);
+
+        MWWorld::MoonModel moon = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+            axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+        MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+        MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+        MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+        MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+        EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+        EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+        EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+        EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+    }
+
+    // OFFSETS
+
+    TEST(MWWorldWeatherTest, secundaShouldApplyIncrementOffsetAfterFirstLoop)
+    {
+        float dailyIncrement = 1.2f;
+        float speed = 0.6f;
+        float fadeEndAngle = 30.0f;
+        float fadeStartAngle = 50.0f;
+        float moonShadowEarlyFadeAngle = 0.5f;
+        float fadeInStart = 14.0f;
+        float fadeInFinish = 15.0f;
+        float fadeOutStart = 7.0f;
+        float fadeOutFinish = 10.0f;
+        float axisOffset = 50.0f;
+
+        // Days 8 and 32, 3:16
+        TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+        timeStampBefore += (24.0f * 8 + 3.0f + 15.0f / 60.0f);
+        timeStampAfter += (24.0f * 8 + 3.0f + 17.0f / 60.0f);
+        timeStampBeforePostLoop += (24.0f * 32 + 3.0f + 15.0f / 60.0f);
+        timeStampAfterPostLoop += (24.0f * 32 + 3.0f + 17.0f / 60.0f);
+
+        MWWorld::MoonModel moon = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+            axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+        MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+        MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+        MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+        MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+        EXPECT_LE(beforeState.mMoonAlpha, 0.0f);
+        EXPECT_GT(afterState.mMoonAlpha, 0.0f);
+        EXPECT_LE(beforeStatePostLoop.mMoonAlpha, 0.0f);
+        EXPECT_GT(afterStatePostLoop.mMoonAlpha, 0.0f);
+    }
+
+    TEST(MWWorldWeatherTest, moonWithLowIncrementShouldApplyIncrementOffsetAfterCycle)
+    {
+        float dailyIncrement = 0.9f;
+        float speed = 0.5f;
+        float fadeEndAngle = 40.0f;
+        float fadeStartAngle = 50.0f;
+        float moonShadowEarlyFadeAngle = 0.5f;
+        float fadeInStart = 0.0f;
+        float fadeInFinish = 0.0f;
+        float fadeOutStart = 0.0f;
+        float fadeOutFinish = 0.0f;
+        float axisOffset = 35.0f;
+
+        // Days 7 and 31, 1:44
+        TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+        timeStampBefore += (24.0f * 7 + 1.0f + 43.0f / 60.0f);
+        timeStampAfter += (24.0f * 7 + 1.0f + 45.0f / 60.0f);
+        timeStampBeforePostLoop += (24.0f * 31 + 1.0f + 43.0f / 60.0f);
+        timeStampAfterPostLoop += (24.0f * 31 + 1.0f + 45.0f / 60.0f);
+
+        MWWorld::MoonModel moon = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+            axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+        MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+        MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+        MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+        MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+        EXPECT_LE(beforeState.mMoonAlpha, 0.0f);
+        EXPECT_GT(afterState.mMoonAlpha, 0.0f);
+        EXPECT_LE(beforeStatePostLoop.mMoonAlpha, 0.0f);
+        EXPECT_GT(afterStatePostLoop.mMoonAlpha, 0.0f);
+    }
+
+    TEST(MWWorldWeatherTest, masserShouldApplyIncrementOffsetAfterCycle)
+    {
+        float dailyIncrement = 1.0f;
+        float speed = 0.5f;
+        float fadeEndAngle = 40.0f;
+        float fadeStartAngle = 50.0f;
+        float moonShadowEarlyFadeAngle = 0.5f;
+        float fadeInStart = 0.0f;
+        float fadeInFinish = 0.0f;
+        float fadeOutStart = 0.0f;
+        float fadeOutFinish = 0.0f;
+        float axisOffset = 35.0f;
+
+        // Days 4 and 28, 1:02
+        TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+        timeStampBefore += (24.0f * 4 + 1.0f + 1.0f / 60.0f);
+        timeStampAfter += (24.0f * 4 + 1.0f + 3.0f / 60.0f);
+        timeStampBeforePostLoop += (24.0f * 28 + 1.0f + 1.0f / 60.0f);
+        timeStampAfterPostLoop += (24.0f * 28 + 1.0f + 3.0f / 60.0f);
+
+        MWWorld::MoonModel moon = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+            axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+        MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+        MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+        MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+        MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+        EXPECT_LE(beforeState.mMoonAlpha, 0.0f);
+        EXPECT_GT(afterState.mMoonAlpha, 0.0f);
+        EXPECT_LE(beforeStatePostLoop.mMoonAlpha, 0.0f);
+        EXPECT_GT(afterStatePostLoop.mMoonAlpha, 0.0f);
+    }
+
+    TEST(MWWorldWeatherTest, secundaShouldApplyIncrementOffsetAfterCycle)
+    {
+        float dailyIncrement = 1.2f;
+        float speed = 0.6f;
+        float fadeEndAngle = 30.0f;
+        float fadeStartAngle = 50.0f;
+        float moonShadowEarlyFadeAngle = 0.5f;
+        float fadeInStart = 0.0f;
+        float fadeInFinish = 0.0f;
+        float fadeOutStart = 0.0f;
+        float fadeOutFinish = 0.0f;
+        float axisOffset = 50.0f;
+
+        // Days 3 and 27, 2:04
+        TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+        timeStampBefore += (24.0f * 3 + 2.0f + 3.0f / 60.0f);
+        timeStampAfter += (24.0f * 3 + 2.0f + 5.0f / 60.0f);
+        timeStampBeforePostLoop += (24.0f * 27 + 2.0f + 3.0f / 60.0f);
+        timeStampAfterPostLoop += (24.0f * 27 + 2.0f + 5.0f / 60.0f);
+
+        MWWorld::MoonModel moon = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+            axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+        MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+        MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+        MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+        MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+        EXPECT_LE(beforeState.mMoonAlpha, 0.0f);
+        EXPECT_GT(afterState.mMoonAlpha, 0.0f);
+        EXPECT_LE(beforeStatePostLoop.mMoonAlpha, 0.0f);
+        EXPECT_GT(afterStatePostLoop.mMoonAlpha, 0.0f);
+    }
+
+    TEST(MWWorldWeatherTest, moonWithIncreasedSpeedShouldApplyIncrementOffsetAfterCycle)
+    {
+        float dailyIncrement = 1.2f;
+        float speed = 1.6f;
+        float fadeEndAngle = 30.0f;
+        float fadeStartAngle = 50.0f;
+        float moonShadowEarlyFadeAngle = 0.5f;
+        float fadeInStart = 0.0f;
+        float fadeInFinish = 0.0f;
+        float fadeOutStart = 0.0f;
+        float fadeOutFinish = 0.0f;
+        float axisOffset = 50.0f;
+
+        // Days 4 and 28, 1:13
+        TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+        timeStampBefore += (24.0f * 4 + 1.0f + 12.0f / 60.0f);
+        timeStampAfter += (24.0f * 4 + 1.0f + 14.0f / 60.0f);
+        timeStampBeforePostLoop += (24.0f * 28 + 1.0f + 12.0f / 60.0f);
+        timeStampAfterPostLoop += (24.0f * 28 + 1.0f + 14.0f / 60.0f);
+
+        MWWorld::MoonModel moon = MWWorld::MoonModel("", fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+            axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+        MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+        MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+        MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+        MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+        EXPECT_LE(beforeState.mMoonAlpha, 0.0f);
+        EXPECT_GT(afterState.mMoonAlpha, 0.0f);
+        EXPECT_LE(beforeStatePostLoop.mMoonAlpha, 0.0f);
+        EXPECT_GT(afterStatePostLoop.mMoonAlpha, 0.0f);
+    }
+}