diff --git a/apps/openmw/mwrender/sky.cpp b/apps/openmw/mwrender/sky.cpp
index 7ba490b92..070f941d6 100644
--- a/apps/openmw/mwrender/sky.cpp
+++ b/apps/openmw/mwrender/sky.cpp
@@ -941,10 +941,10 @@ public:
     Moon(osg::Group* parentNode, Resource::ImageManager& imageManager, float scaleFactor, Type type)
         : CelestialBody(parentNode, scaleFactor, 2)
         , mType(type)
-        , mPhase(MoonState::Phase_Unspecified)
+        , mPhase(MoonState::Phase::Unspecified)
         , mUpdater(new Updater(imageManager))
     {
-        setPhase(MoonState::Phase_Full);
+        setPhase(MoonState::Phase::Full);
         setVisible(true);
 
         mGeom->addUpdateCallback(mUpdater);
@@ -993,14 +993,14 @@ public:
 
     unsigned int getPhaseInt() const
     {
-        if      (mPhase == MoonState::Phase_New)              return 0;
-        else if (mPhase == MoonState::Phase_WaxingCrescent)   return 1;
-        else if (mPhase == MoonState::Phase_WaningCrescent)   return 1;
-        else if (mPhase == MoonState::Phase_FirstQuarter)     return 2;
-        else if (mPhase == MoonState::Phase_ThirdQuarter)     return 2;
-        else if (mPhase == MoonState::Phase_WaxingGibbous)    return 3;
-        else if (mPhase == MoonState::Phase_WaningGibbous)    return 3;
-        else if (mPhase == MoonState::Phase_Full)             return 4;
+        if      (mPhase == MoonState::Phase::New)              return 0;
+        else if (mPhase == MoonState::Phase::WaxingCrescent)   return 1;
+        else if (mPhase == MoonState::Phase::WaningCrescent)   return 1;
+        else if (mPhase == MoonState::Phase::FirstQuarter)     return 2;
+        else if (mPhase == MoonState::Phase::ThirdQuarter)     return 2;
+        else if (mPhase == MoonState::Phase::WaxingGibbous)    return 3;
+        else if (mPhase == MoonState::Phase::WaningGibbous)    return 3;
+        else if (mPhase == MoonState::Phase::Full)             return 4;
         return 0;
     }
 
@@ -1090,14 +1090,14 @@ private:
         else
             textureName += "masser_";
 
-        if     (phase == MoonState::Phase_New)            textureName += "new";
-        else if(phase == MoonState::Phase_WaxingCrescent) textureName += "one_wax";
-        else if(phase == MoonState::Phase_FirstQuarter)   textureName += "half_wax";
-        else if(phase == MoonState::Phase_WaxingGibbous)  textureName += "three_wax";
-        else if(phase == MoonState::Phase_WaningCrescent) textureName += "one_wan";
-        else if(phase == MoonState::Phase_ThirdQuarter)   textureName += "half_wan";
-        else if(phase == MoonState::Phase_WaningGibbous)  textureName += "three_wan";
-        else if(phase == MoonState::Phase_Full)           textureName += "full";
+        if     (phase == MoonState::Phase::New)            textureName += "new";
+        else if(phase == MoonState::Phase::WaxingCrescent) textureName += "one_wax";
+        else if(phase == MoonState::Phase::FirstQuarter)   textureName += "half_wax";
+        else if(phase == MoonState::Phase::WaxingGibbous)  textureName += "three_wax";
+        else if(phase == MoonState::Phase::WaningCrescent) textureName += "one_wan";
+        else if(phase == MoonState::Phase::ThirdQuarter)   textureName += "half_wan";
+        else if(phase == MoonState::Phase::WaningGibbous)  textureName += "three_wan";
+        else if(phase == MoonState::Phase::Full)           textureName += "full";
 
         textureName += ".dds";
 
diff --git a/apps/openmw/mwrender/sky.hpp b/apps/openmw/mwrender/sky.hpp
index 9727529d9..cf697bd44 100644
--- a/apps/openmw/mwrender/sky.hpp
+++ b/apps/openmw/mwrender/sky.hpp
@@ -99,17 +99,17 @@ namespace MWRender
 
     struct MoonState
     {
-        enum Phase
+        enum class Phase
         {
-            Phase_Full = 0,
-            Phase_WaningGibbous,
-            Phase_ThirdQuarter,
-            Phase_WaningCrescent,
-            Phase_New,
-            Phase_WaxingCrescent,
-            Phase_FirstQuarter,
-            Phase_WaxingGibbous,
-            Phase_Unspecified
+            Full = 0,
+            WaningGibbous,
+            ThirdQuarter,
+            WaningCrescent,
+            New,
+            WaxingCrescent,
+            FirstQuarter,
+            WaxingGibbous,
+            Unspecified
         };
 
         float mRotationFromHorizon;
diff --git a/apps/openmw/mwworld/weather.cpp b/apps/openmw/mwworld/weather.cpp
index 2f054488b..6a4a227a4 100644
--- a/apps/openmw/mwworld/weather.cpp
+++ b/apps/openmw/mwworld/weather.cpp
@@ -370,7 +370,7 @@ MWRender::MoonState MoonModel::calculateState(const TimeStamp& gameTime) const
         {
             rotationFromHorizon,
             mAxisOffset, // Reverse engineered from Morrowind's scene graph rotation matrices.
-            static_cast<MWRender::MoonState::Phase>(phase(gameTime)),
+            phase(gameTime),
             shadowBlend(rotationFromHorizon),
             earlyMoonShadowAlpha(rotationFromHorizon) * hourlyAlpha(gameTime.getHour())
         };
@@ -439,17 +439,15 @@ inline float MoonModel::rotation(float hours) const
     return 15.0f * mSpeed * hours;
 }
 
-inline unsigned int MoonModel::phase(const TimeStamp& gameTime) const
+MWRender::MoonState::Phase MoonModel::phase(const TimeStamp& gameTime) const
 {
     // Morrowind starts with a full moon on 16 Last Seed and then begins to wane 17 Last Seed, working on 3 day phase cycle.
-    // Note: this is an internal helper, and as such we don't want to return MWRender::MoonState::Phase since we can't
-    // forward declare it (C++11 strongly typed enums solve this).
 
     // If the moon didn't rise yet today, use yesterday's moon phase.
     if(gameTime.getHour() < moonRiseHour(gameTime.getDay()))
-        return (gameTime.getDay() / 3) % 8;
+        return static_cast<MWRender::MoonState::Phase>((gameTime.getDay() / 3) % 8);
     else
-        return ((gameTime.getDay() + 1) / 3) % 8;
+        return static_cast<MWRender::MoonState::Phase>(((gameTime.getDay() + 1) / 3) % 8);
 }
 
 inline float MoonModel::shadowBlend(float angle) const
diff --git a/apps/openmw/mwworld/weather.hpp b/apps/openmw/mwworld/weather.hpp
index 696f7c688..92f2ce6a4 100644
--- a/apps/openmw/mwworld/weather.hpp
+++ b/apps/openmw/mwworld/weather.hpp
@@ -24,6 +24,7 @@ namespace ESM
 namespace MWRender
 {
     class RenderingManager;
+    enum class MoonState::Phase;
 }
 
 namespace Loading
@@ -261,7 +262,7 @@ namespace MWWorld
         float angle(const TimeStamp& gameTime) const;
         float moonRiseHour(unsigned int daysPassed) const;
         float rotation(float hours) const;
-        unsigned int phase(const TimeStamp& gameTime) const;
+        MWRender::MoonState::Phase phase(const TimeStamp& gameTime) const;
         float shadowBlend(float angle) const;
         float hourlyAlpha(float gameHour) const;
         float earlyMoonShadowAlpha(float angle) const;