snort updates and changes to snort.conf

I know this is not really the place for this question but I have had no luck elsewhere. Currently, snort is set to update to the newest rule set on a daily basis, which is what I want. However, I also need to suppress some SIDS, which I have always done by editing the snort.conf file. When the updates occur, it appears as if snort.conf is overwritten with a new version, as the changes I make to the file do not last more than 24 hours before disappearing out of the snort.conf. Am I correct in assuming this is what is occurring? Is there any other way to easily suppress events without having to edit the file after each update?