diff --git a/vendor/clouds3d.js b/vendor/clouds3d.js
index 1f88c75..1cca77f 100644
--- a/vendor/clouds3d.js
+++ b/vendor/clouds3d.js
@@ -5742,7 +5742,7 @@ var CT2_VERT_SRC = [
 ].join('\n');
 
 var CT2_FRAG_SRC = [
-    'precision mediump float;',
+    'precision highp float;',
     'uniform float uDay;',
     'uniform float uNight;',
     'uniform float uTime;',