Just keep in mind that the registration is just if you want to "show" your car and park with all the other cars. You can still come as a spectator...not sure about the parking, etc. but that is an option if you want to still go.
Next person to post a weather report for rain without backing it up with a real forecast will be getting a visit from me! :smash: Or am I really just not looking at right weather reports...weather looks perfect for Wed.