Board Thread:Support Requests - Getting Technical/@comment-2009398-20150327131012/@comment-5288784-20150327131945

Go to MediaWiki:Common.js and add double slashes (//) at the beginning of the last line to get something like this:

//importScriptPage('MediaWiki:Snow.js','c');

This will disable the snow. When you want it next year, just remove the slashes.