My Mac doesn't show correct time

I am living in Guadalajara, Mexico, central time. When I adjust the computer to auto time it shows that I am in Guadalajara, and the central time zone, but for some reason it thinks I am 2 hours ahead of the real time. I am not using Windows or anything else on the computer, and this is really messing up my calendar syncs between comp and Ipad 2. Please help

You'll need to find out if this is the same on all Macs in your locale. If it is then the problem is with Apples Daylight saving file and only they can fix that, you just have to find a work around until they do.

If its just your computer then you have a setting wrong. I see Mexico has 4 Time Zone options in System Preferences > Date & Time to choose from are they all wrong?

I'd also check you are using the correct Time Server in Date & Time > Set date and time automatically: