While I took a crack at where before, WHEN may be more important. If you think evacuation is advisable, you should leave well before it becomes mandatory. If not, you will likely be in an Interstate parking lot.

Also helpful will be alternate routes. Locally, both I-95 and the Beeline (route between Orlando and beaches) were overloaded. By avoiding them, I was able to easily get past Orlando.

Finally, there is no guaranteed safe place. However, from Columbia (or another temporary haven) you can always head in a diiferent direction if the forecast warrants.