Hi @jrodricks,
I guess you have seen these discussions, but just in case you missed them:
Try here: New Tempest owner: on how to extract data - #15 by scott.reno
I read of one person using google sheets to create a text file of history as a backup.
There are some discussions regarding the 2000 line limit but I do not recall anyone providing an actual solution to how they have got around it. Some discussion here:
And of course there are several other options such as installing weewx.
I hope this might be of some help
cheers Ian 