How can I cache a web application locally

In my company, we have a report generation team which maintains a local web application which is horribly slow. These reports get generated weekly. The data for these reports reside inside a database which gets queried through this report portal. I cannot suggest them to change the application in anyway (like memcache etc.) the only option I have is to somehow save these pages locally and relay.

As these are not static pages(they use database to fetch the data), I want to know is there anyway I can store these pages locally by running a cronjob and then have the super fast access for me and my team.

PS:This application doesn't have any authentication these are plain diffs of two files stored in the database.