Static vs Cache

I am hitting database and retrieving data. The data will be changed only on daily basis. I want to store the data in the form of cache.

Right now, I am using static class object with dictionary as a cache.

I am not using any of the feature of cache object like dependency, sliding expiration etc, So I am sticking to static object to store the data and share it across. I am manually making static object as thread safe. Is there any disadvantage of using static variable instead of cache object?

Where is static data stored? I know it gets destroyed when we do IIS Reset. Is it stored in IIS memory? 

Where is cache data stored?

Thanks for the help in advance

Thanks